Remove unsupported Local-only

Note: It’s still being considered to be added, but in a different way so removing it for now

app/javascript/flavours/glitch/features/compose/components/options.js

@@ -342,12 +342,6 @@ class ComposerOptions extends ImmutablePureComponent {
           disabled={disabled}
           icon='ellipsis-h'
           items={advancedOptions ? [
-            {
-              meta: <FormattedMessage {...messages.local_only_long} />,
-              name: 'do_not_federate',
-              on: advancedOptions.get('do_not_federate'),
-              text: <FormattedMessage {...messages.local_only_short} />,
-            },
             {
               meta: <FormattedMessage {...messages.threaded_mode_long} />,
               name: 'threaded_mode',