Update dependency rubocop-rspec to v2.30.0

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
rubocop-rspec (changelog)	'2.29.2' -> '2.30.0'

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Release Notes

rubocop/rubocop-rspec (rubocop-rspec)

### [`v2.30.0`](https://togithub.com/rubocop/rubocop-rspec/releases/tag/v2.30.0): RuboCop RSpec v2.30.0 [Compare Source](https://togithub.com/rubocop/rubocop-rspec/compare/v2.29.2...v2.30.0) - Add new `RSpec/ExpectInLet` cop. ([@​yasu551]) [@​yasu551]: https://togithub.com/yasu551

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Configuration

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♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box

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[yegor256]

@rultor please, try to merge, since 2 checks have passed

[rultor]

@rultor please, try to merge, since 2 checks have passed

@yegor256 OK, I'll try to merge now. You can check the progress of the merge here

[rultor]

@rultor please, try to merge, since 2 checks have passed

@yegor256 Done! FYI, the full log is here (took me 17min)