Enable Lint/RedundantCopDisableDirective cop in grace period

What does this MR do and why?

Enable Lint/RedundantCopDisableDirective cop in grace period

According to https://docs.gitlab.com/ee/development/rubocop_development_guide.html#cop-grace-period, we should enable new cops in grace period.

References

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#376133 (closed)

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Related to #376133 (closed)