Update warning message string for k8s version compatibility check

**Description**
The warning message earlier was not formatted well enough. Made it explicitly look like a warning.

**Testing Done**
- Added unit test case to check if the warning will be displayed or not.
- Checking the warning color to be yellow.

Author: papriwal

src/sagemaker/hyperpod/common/utils.py

@@ -487,7 +487,7 @@ def verify_kubernetes_version_compatibility(logger) -> bool:
                     click.secho(
                         f"\nWARNING: Kubernetes client version {client_version_str} is incompatible with server {server_version_str}. "
                         f"Server requires minimum client version {min_major}.{min_minor}. "
-                        f"\nPlease update kubernetes Python client: pip install --upgrade kubernetes>={min_major}.{min_minor}.0",
+                        f"\nPlease update Kubernetes Python Client: pip install --upgrade kubernetes>={min_major}.{min_minor}.0",
                         fg="yellow"
                     )
                     is_compatible = False