updated the script for pod push

[aslam9691]

Update release script: Add validation checks and retry logic for CocoaPods

This pull request updates the release_cocoapod.sh script to improve the robustness of the release workflow:

1. Skip Push if Already Published: Added a check to verify if the pod version already exists on CocoaPods Trunk before attempting a push.
2. Improved Validation: The script now strictly ensures that pod validation passes before proceeding with the push.
3. Resilience Against Network Errors: If pod trunk push fails due to a server error (e.g., HTTP 500) but the pod was actually published, the script waits 15 seconds to verify the status via pod trunk info. If the push truly failed, it now performs a single retry.