PluginExtensions: Added onClick to link as a replacement for the command type (#65837)

* Added onClick to the link and made path optional.

* Added type to the import.

* revert(plugin-extensions): put back isPromise utility function

* Minor update to the isPromise function.

* added onClick in the panel menu item.

---------

Co-authored-by: Jack Westbrook <jack.westbrook@gmail.com>
Co-authored-by: Levente Balogh <balogh.levente.hu@gmail.com>

packages/grafana-runtime/src/services/pluginExtensions/utils.test.ts

@@ -15,6 +15,17 @@ describe('Plugin Extensions / Utils', () => {
           path: '...',
         } as PluginExtension)
       ).toBe(true);
+
+      expect(
+        isPluginExtensionLink({
+          id: 'id',
+          pluginId: 'plugin-id',
+          type: PluginExtensionTypes.link,
+          title: 'Title',
+          description: 'Description',
+          onClick: () => {},
+        } as PluginExtension)
+      ).toBe(true);
     });
     test('should return FALSE if the object is NOT a link extension', () => {
       expect(

packages/grafana-runtime/src/services/pluginExtensions/utils.ts

@@ -4,6 +4,5 @@ export function isPluginExtensionLink(extension: PluginExtension | undefined): e
   if (!extension) {
     return false;
   }
-
-  return extension.type === PluginExtensionTypes.link && 'path' in extension;
+  return extension.type === PluginExtensionTypes.link && ('path' in extension || 'onClick' in extension);
 }