chore(appsec): don't load appsec modules (iast) [backport 2.19] (#12350)

backports 
#11931 
#12184
#12212
#12320

to 2.19

## Checklist
- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [x] Reviewer has checked that all the criteria below are met 
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

---------

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Christophe Papazian <[email protected]>

Author: 3 people

.circleci/config.templ.yml

@@ -404,25 +404,12 @@ jobs:
           paths:
             - "."
 
-  appsec_iast_packages:
-    <<: *machine_executor
-    parallelism: 5
-    steps:
-      - when:
-          condition:
-            matches: { pattern: "main", value: << pipeline.git.branch >> }
-          steps:
-            - run_test:
-                pattern: 'appsec_iast_packages'
-                snapshot: true
-      - run: echo "This test is skipped outside of main branch"
-
-  appsec_integrations:
+  appsec_integrations_pygoat:
     <<: *machine_executor
     parallelism: 13
     steps:
       - run_test:
-          pattern: 'appsec_integrations'
+          pattern: 'appsec_integrations_pygoat'
           snapshot: true
           run_agent_checks: false
           docker_services: "pygoat"