Uninstalling a platform or library does not update the version SELECT drop-down

[ubidefeo]

Describe the bug
Installing a platform or a library refreshes the boards/libraries manager tab, displaying the version older than the one just installed in the drop-down menu as a pre-selected option (for downgrade).
Uninstalling leaves the select menu in its last state, with the previous version selected, not the latest available

To Reproduce
Steps to reproduce the behavior:

1. Install a platform or a library at its latest version
2. verify that the drop-down changes to the older version
3. uninstall the platform
4. verify that the drop-down has not changed

Expected behavior
uninstalling should reset the position of the drop-down

Screenshots
before uninstalling

after uninstalling

Desktop (please complete the following information):

• OS: Mac OS Big Sur
• Version: 11.2.3

[ubidefeo]

this issue is not present in RC9

[per1234]

I can still reproduce the issue with the latest build (2.0.0-rc9-snapshot-55927ac). However, I think it is fine to consider it a "wontfix", since the behavior is unlikely to cause problems in real world usage.