CoreCronetEnd2EndTests testCompressedPayload assertion failure

[dennycd]

See samples from run

https://source.cloud.google.com/results/invocations/41df2ac0-fbb6-48db-a03c-a3c82e02af45/targets/github%2Fgrpc%2Frun_tests%2Fobjc_macos_opt_native%2Fios-test-cronettests/tests

The following ObjC test failed

• CoreCronetEnd2EndTests::testCompressedPayload which invokes c-core's following test
  • compressed_payload (test_invoke_request_with_disabled_algorithm)

With assert at

https://github.com/grpc/grpc/blob/409c732813fdee5dadd2a2a14fd5972751443cb1/test/core/end2end/tests/compressed_payload.cc#L209