[Glitch] Convert dropdown_menu state to Typescript

Port 4b7bc1f07c to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/actions/dropdown_menu.ts

@@ -0,0 +1,11 @@
+import { createAction } from '@reduxjs/toolkit';
+
+export const openDropdownMenu = createAction<{
+  id: string;
+  keyboard: boolean;
+  scrollKey: string;
+}>('dropdownMenu/open');
+
+export const closeDropdownMenu = createAction<{ id: string }>(
+  'dropdownMenu/close',
+);