Closing the Search tab should clear highlighting in editors (or hide them)

[ubidefeo]

Describe the bug
When I use the new Search tab it highlights the found instances in any open editor, but once I close the tab the highlight remains, causing a confusing scenario

To Reproduce
Steps to reproduce the behavior:

1. open the search tab
2. search for something which is in your code (any tab)
3. Close the search sidebar
4. look at the text still be highlighted

Expected behavior
two options:

• clearing the search field on close
• hiding the highlight and show it again when the tab is open

Screenshots

Desktop (please complete the following information):

• OS: Mac OS 10.15.7
• Version: 2.0.0 Beta 4