CreateSecretStorageDialog: stop using deprecated APIs (#11635)

* Add some tests for `CreateSecretStorageDialog`

* CreateSecretStorageDialog: stop using deprecated APIs

test/test-utils/test-utils.ts

@@ -60,7 +60,7 @@ import MatrixClientBackedSettingsHandler from "../../src/settings/handlers/Matri
  * the react context, we can get rid of this and just inject a test client
  * via the context instead.
  *
- * See also `getMockClientWithEventEmitter` which does something similar but different.
+ * See also {@link getMockClientWithEventEmitter} which does something similar but different.
  */
 export function stubClient(): MatrixClient {
     const client = createTestClient();