Remove temporary test code.

Author: ehsannas

Firestore/Example/Tests/Util/FSTIntegrationTestCase.mm

@@ -198,12 +198,6 @@ + (void)setUpDefaults {
   // SSL certs.
   NSString *project = [[NSProcessInfo processInfo] environment][@"PROJECT_ID"];
   NSString *targetBackend = [[NSProcessInfo processInfo] environment][@"TARGET_BACKEND"];
-
-  // Forcing use of nightly.
-  // TODO(types/ehsann): remove this before merging into main.
-  targetBackend = @"nightly";
-  project = @"firestore-sdk-nightly";
-
   NSString *host;
   if (targetBackend) {
     if ([targetBackend isEqualToString:@"emulator"]) {