Update migration and CSS files to remove trailing whitespace

- Cleaned up trailing whitespace in migration file `remove_unique_game_constraint.rb` to maintain code quality.
- Removed unnecessary whitespace from CSS files for `flag-station-minigame.css` and `vm-launcher-minigame.css`, ensuring cleaner stylesheets.
- Tidied up JavaScript file `hacktivity-cable.js` by eliminating trailing whitespace, improving readability and consistency across the codebase.

db/migrate/20251128000001_remove_unique_game_constraint.rb

@@ -20,3 +20,4 @@ end
 
 
 
+