Revert "Rename all test files from JS -> ES6"

This reverts commit 2abe85b8344de1102c1589a9ac9421a8b296f2b5.

test/javascripts/admin/controllers/admin-customize-themes-show-test.js

@@ -1,53 +0,0 @@
-import { mapRoutes } from "discourse/mapping-router";
-import Theme from "admin/models/theme";
-
-moduleFor("controller:admin-customize-themes-show", {
-  beforeEach() {
-    this.registry.register("router:main", mapRoutes());
-  },
-  needs: ["controller:adminUser"]
-});
-
-QUnit.test("can display source url for remote themes", function(assert) {
-  const repoUrl = "https://github.com/discourse/discourse-brand-header.git";
-  const remoteTheme = Theme.create({
-    id: 2,
-    default: true,
-    name: "default",
-    remote_theme: {
-      remote_url: repoUrl
-    }
-  });
-  const controller = this.subject({
-    model: remoteTheme
-  });
-
-  assert.deepEqual(
-    controller.get("remoteThemeLink"),
-    repoUrl,
-    "returns theme's repo URL"
-  );
-});
-
-QUnit.test("can display source url for remote theme branches", function(
-  assert
-) {
-  const remoteTheme = Theme.create({
-    id: 2,
-    default: true,
-    name: "default",
-    remote_theme: {
-      remote_url: "https://github.com/discourse/discourse-brand-header.git",
-      branch: "beta"
-    }
-  });
-  const controller = this.subject({
-    model: remoteTheme
-  });
-
-  assert.deepEqual(
-    controller.get("remoteThemeLink"),
-    "https://github.com/discourse/discourse-brand-header/tree/beta",
-    "returns theme's repo URL to branch"
-  );
-});