DEV: refactors admin-plugins/admin-site-settings (#15244)

- drops jQuery usage
- removes apparently useless clearfix
- uses @action
- drops unused clearFilter function in admin-plugins

app/assets/javascripts/admin/addon/controllers/admin-plugins.js

@@ -1,3 +1,4 @@
+import { action } from "@ember/object";
 import Controller from "@ember/controller";
 import discourseComputed from "discourse-common/utils/decorators";
 
@@ -13,13 +14,11 @@ export default Controller.extend({
       .compact();
   },
 
-  actions: {
-    clearFilter() {
-      this.setProperties({ filter: "", onlyOverridden: false });
-    },
-
-    toggleMenu() {
-      $(".admin-detail").toggleClass("mobile-closed mobile-open");
-    },
+  @action
+  toggleMenu() {
+    const adminDetail = document.querySelector(".admin-detail");
+    ["mobile-closed", "mobile-open"].forEach((state) => {
+      adminDetail.classList.toggle(state);
+    });
   },
 });

app/assets/javascripts/admin/addon/controllers/admin-site-settings.js

@@ -5,6 +5,7 @@ import { alias } from "@ember/object/computed";
 import discourseDebounce from "discourse-common/lib/debounce";
 import { isEmpty } from "@ember/utils";
 import { observes } from "discourse-common/utils/decorators";
+import { action } from "@ember/object";
 
 export default Controller.extend({
   filter: null,
@@ -126,13 +127,16 @@ export default Controller.extend({
     );
   },
 
-  actions: {
-    clearFilter() {
-      this.setProperties({ filter: "", onlyOverridden: false });
-    },
+  @action
+  clearFilter() {
+    this.setProperties({ filter: "", onlyOverridden: false });
+  },
 
-    toggleMenu() {
-      $(".admin-detail").toggleClass("mobile-closed mobile-open");
-    },
+  @action
+  toggleMenu() {
+    const adminDetail = document.querySelector(".admin-detail");
+    ["mobile-closed", "mobile-open"].forEach((state) => {
+      adminDetail.classList.toggle(state);
+    });
   },
 });

app/assets/javascripts/admin/addon/templates/plugins.hbs

@@ -26,5 +26,3 @@
 <div class="admin-detail pull-left mobile-closed">
   {{outlet}}
 </div>
-
-<div class="clearfix"></div>