Added skip_warning ability to deprecators for tests

[keshavbiswa]

Motivation / Background

Fixes: #2948

This Pull Request has been created because We want the ability to silence output warnings for Deprecated Generators in tests.

Checklist

Before submitting the PR make sure the following are checked:

• [x] This Pull Request is related to one change. Changes that are unrelated should be opened in separate PRs.
• [x] Commit message has a detailed description of what changed and why. If this PR fixes a related issue include it in the commit message. Ex: [Fix #issue-number]
• [x] Tests are added or updated if you fix a bug, refactor something, or add a feature.
• [x] Tests and Rubocop are passing before submitting your proposed changes.

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• [ ] Double-check the existing generators documentation to make sure the new generator you want to add doesn't already exist.
• [ ] You've reviewed and followed the Contributing guidelines.