Inconsistent filter dropdown widths

### StatGPT Admin Frontend version

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### What steps will reproduce the bug?

1. Open StatGPT admin app
2. Switch to Audit Logs
3. Click on the filter icon in 'Action' column -> note its width
4. Click on the filter icon in 'Entity type' column -> note its width

**Actual result:** the width of the filters is slightly different, human eyes catches the difference, especially when the filters are located close to each other.
Note: for example, the same type of filter exists in Channels ->StatGPT Sample -> Grade C datasets -> Validation Status; Indexing Status

**Expected result:** to have any common minimum width. As far as I see this filter is the biggest in our values now and seems to be fine to have the same width for others.

### What is the expected behavior?

_No response_

### What do you see instead?

-

### Additional information

_No response_

Start in the StatGPT admin app's Audit Logs view and inspect the filter dropdowns for the Action and Entity type columns, then compare them with the Validation Status and Indexing Status filters in Channels. Done means these same-type filters share a common minimum width and no longer appear visibly different when shown together.

Written by the indexing model from the issue text.