Fix overflow margin on productivity analytics filter bar

What does this MR do and why?

Fix overflow margin on productivity analytics filter bar

Minor fix for the overflowing input field on small screens for productivity analytics.

Follow up to #414233 (closed)

Screenshots or screen recordings

Before	After

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

• You will need a GitLab Premium license
• Follow the instructions to view productivity analytics
• Resize the screen to a small size

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #414233 (closed)