Adding tab space when pressing `alt + tab`

## Lapce Version
[nightly-5bfc597](https://github.com/lapce/lapce/commit/5bfc5975cd018646d0a86e5dba7c662be6f74462)

## System information
Windows 10

## Describe the bug
Register tab key press in the editor and every text field in the app when pressing `alt + tab` to navigate in windows.

## Additional information


