Added "Close mode" frame in editor preference

[praveen-skp]

Issue: #2297

This pull request adds a "Close mode" frame in the editor preference to make the "Close editors automatically" and "Number of opened editors before closing" grouping clear.

[praveen-skp]

The new UI with "Close mode" grouping

[laeubi]

Close mode as a group name reads a bit strange here, I would expect then having different modes to select but the configuration do not really offer that.

My suggestion would be to merge both settings into one line instead of grouping them e.g.

[ ] Close oldest if there are more than _____ editors open

[github-actions]

Test Results

 1 815 files  ±0   1 815 suites  ±0   1h 36m 33s ⏱️ - 6m 18s
 7 699 tests ±0   7 470 ✅  - 1  228 💤 ±0  1 ❌ +1 
24 258 runs  ±0  23 510 ✅  - 1  747 💤 ±0  1 ❌ +1 

For more details on these failures, see this check.

Results for commit c3d99f0. ± Comparison against base commit 88b1d36.

[BeckerWdf]

Close mode as a group name reads a bit strange here

What about "Closing behaviour"?

[BeckerWdf]

My suggestion would be to merge both settings into one line instead of grouping them

This is also a good idea.