Dried repo_editor editMode codeclimate reported code

app/assets/javascripts/repo/repo_editor.js

@@ -72,18 +72,19 @@ export default class RepoEditor {
         },
 
         editMode() {
+          const panelClassList = document.querySelector('.panel-right').classList;
+          let readOnly = true;
+
           if (this.editMode) {
-            document.querySelector('.panel-right').classList.add('edit-mode');
-            self.monacoEditor.updateOptions({
-              readOnly: false,
-            });
+            panelClassList.add('edit-mode');
           } else {
-            document.querySelector('.panel-right').classList.remove('edit-mode');
-
-            self.monacoEditor.updateOptions({
-              readOnly: true,
-            });
+            panelClassList.remove('edit-mode');
+            readOnly = true;
           }
+
+          self.monacoEditor.updateOptions({
+            readOnly,
+          });
         },
 
         activeFileLabel() {