Fix batch actions being hidden from mobile view (#12183)

On mobile, batch actions are hidden from the settings/admin interface,
but there are several places those actions can only be performed through
batch actions.

This may not look great, but at least it makes the actions available again.

app/javascript/styles/mastodon/tables.scss

@@ -149,10 +149,6 @@ a.table-action-link {
           margin-top: 0;
         }
       }
-
-      @media screen and (max-width: $no-gap-breakpoint) {
-        display: none;
-      }
     }
 
     &__actions,
@@ -174,10 +170,6 @@ a.table-action-link {
       text-align: right;
       padding-right: 16px - 5px;
     }
-
-    @media screen and (max-width: $no-gap-breakpoint) {
-      display: none;
-    }
   }
 
   &__form {
@@ -198,7 +190,7 @@ a.table-action-link {
     background: darken($ui-base-color, 4%);
 
     @media screen and (max-width: $no-gap-breakpoint) {
-      &:first-child {
+      .optional &:first-child {
         border-top: 1px solid darken($ui-base-color, 8%);
       }
     }
@@ -264,6 +256,13 @@ a.table-action-link {
     }
   }
 
+  &.optional .batch-table__toolbar,
+  &.optional .batch-table__row__select {
+    @media screen and (max-width: $no-gap-breakpoint) {
+      display: none;
+    }
+  }
+
   .status__content {
     padding-top: 0;
 

app/views/admin/tags/index.html.haml

@@ -48,7 +48,7 @@
   - Admin::FilterHelper::TAGS_FILTERS.each do |key|
     = hidden_field_tag key, params[key] if params[key].present?
 
-  .batch-table
+  .batch-table.optional
     .batch-table__toolbar
       %label.batch-table__toolbar__select.batch-checkbox-all
         = check_box_tag :batch_checkbox_all, nil, false