Don't error on wrong MR IID in changelog for cherry pick MRs

What does this MR do?

For MRs that include "cherry-pick"/"cherry pick" in their title and that target a stable branch, we shouldn't require a changelog entry. This MR implements this.

Verification MR: !35744 (comment 371685935)

Does this MR meet the acceptance criteria?

Conformity

• Code review guidelines
• Merge request performance guidelines
• Style guides
• Separation of EE specific content