Adjust pull_request_target triggers and enhance security checks

[tonyhoo]

Description

Refactored the CI workflow to adjust pull_request_target triggers for better event specificity and enhanced security checks. This includes limiting the workflow to specific pull request events and ensuring secure handling of secrets.

Related Issue

N/A

Type of Change

• Bug fix
• New feature
• Documentation update
• Performance improvement
• Code refactoring
• Other (please specify)

Checklist

• I have read the CONTRIBUTING document
• My code follows the project's coding style
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have updated the documentation accordingly
• I have added appropriate comments to my code, particularly in hard-to-understand areas

Additional Information

This change aims to optimize the CI process by reducing unnecessary workflow runs and ensuring that sensitive operations are securely handled.

Screenshots (if appropriate)

N/A

Performance Impact

This change should reduce unnecessary CI runs, potentially improving overall performance by conserving computational resources.

Backwards Compatibility

No backwards incompatible changes introduced.

Dependency Changes

No new dependencies introduced or removed.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[suzhoum]

LGTM!