fix(data-service): relax getSearchIndexes error message test (#4981)

This has been causing CI failures on main.

Author: addaleax

packages/data-service/src/data-service.spec.ts

@@ -1144,7 +1144,7 @@ describe('DataService', function () {
           dataService.getSearchIndexes(testNamespace)
         ).to.be.rejectedWith(
           MongoServerError,
-          "Unrecognized pipeline stage name: '$listSearchIndexes'"
+          /Unrecognized pipeline stage name: '\$listSearchIndexes'"|\$listSearchIndexes stage is only allowed on MongoDB Atlas/
         );
       });
     });