Add gitConfig Option to Airflow Helm Chart for Custom Git Configuration

This pull request introduces the following changes:

1. gitConfig Parameter:

   • Added a new parameter, gitConfig, to the Apache Airflow Helm chart. This allows users to specify custom Git configuration settings for the git-sync sidecar container, offering more flexibility in managing Git behavior during DAG synchronization.

2. Airflow API Server Update:

   • Updated the NOTES.txt to reflect the usage of .apiServer instead of .web for Airflow v3 deployments, aligning with the updated configuration style for Airflow v3 and improving compatibility with newer versions of the platform.

🔧 Changes Introduced

• New Configuration Field:

  • dags.gitSync.gitConfig: Accepts a list of Git configuration entries, enabling users to set custom Git configurations such as user identity, credential helpers, and other Git settings.

• Airflow Web to API Server Update:

  • Modified NOTES.txt to replace .web with .apiServer, which is the correct configuration for Airflow v3, ensuring the Helm chart is aligned with the latest Airflow version.

This addition aligns with the existing git-sync capabilities and allows for more tailored Git interactions within Airflow deployments.

🧪 Testing and Validation

• Verified that custom Git configurations specified via gitConfig are correctly applied within the git-sync container.
• Ensured that the addition of gitConfig does not interfere with existing git-sync functionality or other Helm chart configurations.
• Confirmed that the .apiServer setting is correctly used in Airflow v3 and does not affect backward compatibility with Airflow v2.

📚 Documentation

• Updated the Helm chart documentation to include the new gitConfig parameter, with examples demonstrating its usage.
• Adjusted NOTES.txt to reflect the .apiServer setting for Airflow v3 deployments, ensuring correct configuration for Airflow v3 clusters.

🔄 Backward Compatibility

This change is backward compatible. If gitConfig is not specified, the git-sync container will operate with its default Git configuration.

• The change from .web to .apiServer in notes.txt is only relevant for Airflow v3 deployments and does not affect Airflow v2.

📌 Related Issues

This enhancement addresses the need for more customizable Git configurations within the Airflow Helm chart's git-sync setup so it is possible to use all git providers, including Azure DevOps Repos.

By introducing the gitConfig parameter, this update provides users with enhanced control over Git behavior in their Airflow deployments, facilitating more complex and customized workflows.

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