fix scrollToAlignment of TreeWidget to align vscode

[shuyaqian]

Signed-off-by: shuyaqian [email protected]

What it does

To fix when switch files in editor , the selected node is not in the center. theia: vscode:

How to test

Review checklist

• [x] as an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• as a reviewer, I agree to behave in accordance with the review guidelines

[shuyaqian]

I've changed this approach so that the tree node will not scroll to the center whether you click or double-click in the file tree. Scrolls only when you switch the tab. @vince-fugnitto

[shuyaqian]

@vince-fugnitto Can you help to review this pr again?

[vince-fugnitto]

Closing due to inactivity. We can always re-open the pull-request when updates are made.