feat: allow schemas in pipeline files

[lars-reimann]

Closes #1077

Summary of Changes

Pipelines files can now contain schemas.

[github-actions[bot]]

🦙 MegaLinter status: ✅ SUCCESS

Descriptor	Linter	Files	Fixed	Errors	Elapsed time
✅ JSON	eslint-plugin-jsonc	3	0	0	1.46s
✅ JSON	jsonlint	3		0	0.24s
✅ JSON	npm-package-json-lint	yes		no	0.81s
✅ JSON	prettier	3	0	0	0.81s
✅ JSON	v8r	3		0	2.11s
✅ REPOSITORY	git_diff	yes		no	0.21s
✅ TYPESCRIPT	eslint	6	0	0	6.12s
✅ TYPESCRIPT	prettier	6	0	0	1.3s

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 100.00%. Comparing base (e34b3ff) to head (8aa9996).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1080 +/- ## ========================================= Coverage 100.00% 100.00% ========================================= Files 104 104 Lines 20565 20564 -1 Branches 4061 4061 ========================================= - Hits 20565 20564 -1 ```

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[lars-reimann]

:tada: This PR is included in version 0.13.0 :tada:

The release is available on:

• npm package (@latest dist-tag)
• npm package (@latest dist-tag)
• v0.13.0
• GitHub release

Your semantic-release bot :package::rocket: