Fix deprecation.milestone for timeframe arguments

What does this MR do?

This MR changes a usage of deprecation.milestone to reflect the milestone the deprecation happened in, rather than the milestone we expect to remove the deprecation in.

See !44208 (diffs, comment 429917764).

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content