Closes #31574 

Move this button a bit to the left so it doesn't get blocked by the
hitbox of the scrollbar.

Also makes the list entries a bit thicker vertically so that the button
can be `XSmall` instead of `Indicator`-sized again.

Release Notes:

- Debugger Beta: fixed a layout issue that made it hard to click the
remove (`X`) button for entries in the breakpoint list.