[Glitch] Add new ESLint rule requiring explicit button types

Port 6337e036f3 to glitch-soc

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

app/javascript/flavours/glitch/components/dropdown_menu.tsx

@@ -237,6 +237,7 @@ export const DropdownMenu = <Item = MenuItem,>({
           onKeyUp={handleItemKeyUp}
           data-index={i}
           aria-disabled={disabled}
+          type='button'
         >
           <DropdownMenuItemContent item={option} />
         </button>