Undefined symbol when I build an installed cocoa pod of Mediation Test Suite

We are trying to implement the Mediation Test Suite but, we are getting the following error message:

Undefined symbols for architecture arm64: "_kGADSimulatorID", referenced from: _GMTSMediationRequest in GoogleMobileAdsMediationTestSuite(GMTSMediationHelper.o)
"_kGADAdSizeBanner", referenced from: -[GMTSBannerAdLoader initWithAdUnitId:rootViewController:] in GoogleMobileAdsMediationTestSuite(GMTSBannerAdLoader.o)
"_kGADAdLoaderAdTypeNative", referenced from: -[GMTSNativeAdLoader initWithAdUnitId:rootViewController:] in GoogleMobileAdsMediationTestSuite(GMTSNativeAdLoader.o) ld: symbol(s) not found for architecture arm64 clang: error: linker command failed with exit code 1 (use -v to see invocation)