Issue:
Bug: Fix(CI): Update api-reference path in `pr_labeler`



PR #8333 modified the `api-reference` folder structure. Need to update it in `pr_labeler` job

Pull request description:
## Type of Change
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- [x] Bugfix
- [ ] New feature
- [ ] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [x] CI/CD

## Description
<!-- Describe your changes in detail -->
- Updated OpenAPI spec path in `pr_labeler` CI job
- Modified `CODEOWNERS` file to remove deleted folder 

### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [ ] This PR modifies application configuration/environment variables

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Following are the paths where you can find config files:
1. `config`
2. `crates/router/src/configs`
3. `loadtest/config`
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## Motivation and Context
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that will have little conversation).
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Closes #8343

## How did you test it?
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## Checklist
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- [ ] I formatted the code `cargo +nightly fmt --all`
- [ ] I addressed lints thrown by `cargo clippy`
- [x] I reviewed the submitted code
- [ ] I added unit tests for my changes where possible

Testing:

Patch: