message: Allow for optional string
diff: @@ -167,7 +167,8 @@ export class CatalogImportClient implements CatalogImportApi {
  );
  });
  - const appTitle = this.configApi.getString('app.title');
  + const appTitle =
  + this.configApi.getOptionalString('app.title') ?? 'Backstage';
  const appBaseUrl = this.configApi.getString('app.baseUrl');
  const prBody = `This pull request adds a **Backstage entity metadata file** \
  