Address Ruby 3 RuboCop violations

[mokagio]

17ec957 (#21498) switched the expected Ruby version to 3.x (🎉)

Our Ruby linting automation only runs on diffed files so it didn't catch new violations that arose from the migration. The only reason I noticed, actually was because I just happened to modify the Podfile in df0aa0bd25a3cf4fa6313eb3534bd05c959a2a8 (#21344) and got a CI failure. I based this PR off #21344 because I had to fix one of the issues there in order for the linter to pass.

To test: checkout the branch and verify RuboCop doesn't find new violations:

Regression Notes

1. Potential unintended areas of impact – N.A.
2. What I did to test those areas of impact (or what existing automated tests I relied on) – N.A.
3. What automated tests I added (or what prevented me from doing so) – N.A.

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PR submission checklist:

• I have completed the Regression Notes.
• I have considered adding unit tests for my changes. N.A.
• I have considered adding accessibility improvements for my changes. N.A.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary. N.A.

UI changes testing checklist: Not a UI PR.

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	Build Number	pr21541-57473ab
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	Commit	57473ab
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