Improvement to Apex tests sidebar.

[mihailTr-19]

When I run all my Apex tests, and only one of them failed I have to scroll throught all apex tests to find the red mark.
But if I can collapse them to view Apex classes only I could find the class with the error, and after it open that class.

Add collapse all functionality to the Apex tests sidebar.

Like we have it in the Explorer.

[goto-dev-null]

💯 Without this the test pane is unusable. Even just defaulting to having every class collapsed instead of expanded would make it usable; I can't imagine anyone preferring to scroll through through 50x more lines to find 1 file.

A filter/jump-to feature would also make it much more usable IMO. Even with every test file collapsed, it's still a chore to find it in the list.

But I just wanna collapse them more than anything.