feat(codepipeline): GitPullRequestFilter for pipeline trigger (#29128)

### Issue # (if applicable)

Closes #29126.

Related PR: #29127
Perhaps if one merges, the other will cause a conflict.

### Reason for this change

We would be good to trigger pipelines by git pull request filters.

- CFn and API docs
  - https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-codepipeline-pipeline-gitconfiguration.html
  - https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-codepipeline-pipeline-gitpullrequestfilter.html
  - https://docs.aws.amazon.com/codepipeline/latest/APIReference/API_GitPullRequestFilter.html

### Description of changes

Add `gitPullRequestFilter` parameter with new interface into `GitConfiguration` interface.

### Description of how you validated changes

Both unit and integ tests.

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

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*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*