"Redoing" a realtime effect results in a crash

[Ryan-Miller-Audacity]

Describe the bug In testing of #2985, it was noted that after undoing and then redoing an effect attempting to open the effect settings in the Realtime Effect UI results in a crash.

https://user-images.githubusercontent.com/88568755/173657163-ba951b33-6083-4c35-a7a9-6598595f707a.mp4

To Reproduce Steps to reproduce the behavior:

1. Open Audacity
2. Generate a tone/add some audio
3. Add a realtime effect like reverb or wahwah via the effects side panel
4. Click the gear icon, edit the sliders for the effect, and click OK
5. Go to Edit -> Undo
6. Click the gear icon and note the changes were undone
7. Go to Edit -> Redo
8. Click the gear icon
9. Audacity Crashes

Actual behavior Audacity crashes when attempting to open realtime effect settings after "redoing" a previously undone effect

Expected behavior Users should be able to open the effect settings after redoing a previously undone effect

Screenshots Screencast included in the summary above.

Additional information (please complete the following information):

• OS: MacOS Monetery 12.3.1 and Windows 10
• Version: Audacity 3.2.0-alpha-20220614 (commit id: fccf7dc)
• (if relevant) Sound Device: N/A
• Related Pull Request: #2988

Additional context N/A

[petersampsonaudacity]

Testing on W10 with @Paul-Licameli 's branch build "Sidebar bugs": https://github.com/audacity/audacity/actions/runs/2497329369

This now works properly - so PR #3075 fixes this - in Paul's branch

[pietro68]

Verified it is fixed on a3b3b53

[petersampsonaudacity]

Tested on W10 with latest master audacity-win-3.2.0-alpha-20220623+2fd21af-x64-msvc2022

This works fine with no crash

[dozzzzer]

Verified on Win10 & MacOS