linux: Restore ctrl-escape to keymap (#37636)

Closes: https://github.com/zed-industries/zed/issues/37628
Follow-up to: https://github.com/zed-industries/zed/pull/36712

Release Notes:

- linux: Fix for ctrl-escape not escaping the tab switcher.

assets/keymaps/default-linux.json

@@ -16,6 +16,7 @@
       "up": "menu::SelectPrevious",
       "enter": "menu::Confirm",
       "ctrl-enter": "menu::SecondaryConfirm",
+      "ctrl-escape": "menu::Cancel",
       "ctrl-c": "menu::Cancel",
       "escape": "menu::Cancel",
       "alt-shift-enter": "menu::Restart",