Update to 2.25.6
    
    - If Shift+something is pressed and then released, do not swallow the release of the Shift key
      (Resolves: https://github.com/mike-fabian/ibus-typing-booster/issues/504)
    - Decrease grid_row_spacing from 5 to 1 pixels to make the setup tool still fit on a 1024x768 pixel screen