CLOUDP-295785 - add pipeline_main.py extended help (#334)

# Summary

Adding more help information for the `scripts.release.pipeline_main`
python script.

## Proof of Work

```
(venv) ➜  mongodb-kubernetes git:(maciejk/use-ar-related-versions) ✗ python3 -m scripts.release.pipeline_main --help
usage: pipeline_main.py [-h] [-b ] [-p ] [-v ] [-r ] [-s] [--parallel] [--parallel-factor ] image

Builder tool for container images. It allows to push and sign images with multiple architectures using Docker Buildx. By default build information is read from 'build_info.json' file in the project root directory based on the build scenario. It can be inferred from the environment variables or overridden with the '--build-scenario' option.

positional arguments:
  image                 Image name to build. Supported images: meko-tests, operator, mco-tests, readiness-probe, upgrade-hook, database, agent, init-appdb, init-database, init-ops-manager, ops-manager

options:
  -h, --help            show this help message and exit
  -b, --build-scenario
                        Override the build scenario instead of inferring from environment. Options: release, patch, staging, development. Default is to infer from environment variables. For 'development' the 'patch' scenario is used to read values from 'build_info.json'
  -p, --platform        Override the platforms instead of resolving from build scenario. Multi-arch builds are comma-separated. Example: linux/amd64,linux/arm64
  -v, --version         Override the version/tag instead of resolving from build scenario. Default is to infer from environment variables based on the selected scenario.
  -r, --registry        Override the base registry instead of resolving from build scenario
  -s, --sign            If set force image signing. Default is to infer from build scenario.
  --parallel            Build agent images in parallel.
  --parallel-factor     Number of agent builds to run in parallel, defaults to number of cores
```

## Checklist

- [x] Have you linked a jira ticket and/or is the ticket in the title?
- [x] Have you checked whether your jira ticket required DOCSP changes?
- [x] Have you added changelog file?
    - use `skip-changelog` label if not needed
- refer to [Changelog files and Release
Notes](https://github.com/mongodb/mongodb-kubernetes/blob/master/CONTRIBUTING.md#changelog-files-and-release-notes)
section in CONTRIBUTING.md for more details

---------

Co-authored-by: Julien Benhaim <[email protected]>

Author: MaciejKaras

scripts/release/pipeline_main.py

@@ -95,7 +95,7 @@ def build_image(image_name: str, build_configuration: ImageBuildConfiguration):
 def image_build_config_from_args(args) -> ImageBuildConfiguration:
     image = args.image
 
-    build_scenario = get_scenario_from_arg(args.scenario) or BuildScenario.infer_scenario_from_environment()
+    build_scenario = get_scenario_from_arg(args.build_scenario) or BuildScenario.infer_scenario_from_environment()
 
     build_info = load_build_info(build_scenario)
     logger.info(f"image is {image}")
@@ -177,34 +177,75 @@ def _setup_tracing():
 
 def main():
     _setup_tracing()
-    parser = argparse.ArgumentParser(description="Build container images.")
-    parser.add_argument("image", help="Image to build.")  # Required
-    parser.add_argument("--parallel", action="store_true", help="Build images in parallel.")
-    parser.add_argument("--sign", action="store_true", help="Sign images.")
+    supported_images = list(get_builder_function_for_image_name().keys())
+    supported_scenarios = list(BuildScenario)
+
+    parser = argparse.ArgumentParser(
+        description="""Builder tool for container images. It allows to push and sign images with multiple architectures using Docker Buildx.
+By default build information is read from 'build_info.json' file in the project root directory based on the build scenario.
+It can be inferred from the environment variables or overridden with the '--build-scenario' option.""",
+    )
+    parser.add_argument(
+        "image",
+        metavar="image",
+        action="store",
+        type=str,
+        choices=supported_images,
+        help=f"Image name to build. Supported images: {", ".join(supported_images)}",
+    )
     parser.add_argument(
-        "--scenario",
-        choices=list(BuildScenario),
-        help=f"Override the build scenario instead of inferring from environment. Options: release, patch, master, development",
+        "-b",
+        "--build-scenario",
+        metavar="",
+        action="store",
+        type=str,
+        choices=supported_scenarios,
+        help=f"""Override the build scenario instead of inferring from environment. Options: {", ".join(supported_scenarios)}.
+Default is to infer from environment variables. For '{BuildScenario.DEVELOPMENT}' the '{BuildScenario.PATCH}' scenario is used to read values from 'build_info.json'""",
     )
-    # Override arguments for build context and configuration
     parser.add_argument(
+        "-p",
         "--platform",
+        metavar="",
+        action="store",
+        type=str,
         help="Override the platforms instead of resolving from build scenario. Multi-arch builds are comma-separated. Example: linux/amd64,linux/arm64",
     )
     parser.add_argument(
+        "-v",
         "--version",
-        help="Override the version/tag instead of resolving from build scenario",
+        metavar="",
+        action="store",
+        type=str,
+        help="Override the version/tag instead of resolving from build scenario. Default is to infer from environment variables based on the selected scenario.",
     )
     parser.add_argument(
+        "-r",
         "--registry",
+        metavar="",
+        action="store",
+        type=str,
         help="Override the base registry instead of resolving from build scenario",
     )
+    parser.add_argument(
+        "-s",
+        "--sign",
+        action="store_true",
+        help="If set force image signing. Default is to infer from build scenario.",
+    )
     # For agent builds
+    parser.add_argument(
+        "--parallel",
+        action="store_true",
+        help="Build agent images in parallel.",
+    )
     parser.add_argument(
         "--parallel-factor",
+        metavar="",
         default=0,
+        action="store",
         type=int,
-        help="Number of builds to run in parallel, defaults to number of cores",
+        help="Number of agent builds to run in parallel, defaults to number of cores",
     )
 
     args = parser.parse_args()