test: AddrFamilyAwareSocketOptionImplTest.V6EmptyOptionNames fails in coverage

[lizan]

Description:
It doesn't fail on CircleCI since in the CI coverage tests runs with --test_env=ENVOY_IP_TEST_VERSIONS=v4only.

I suspect it is related to the Singleton injection, but didn't look it closely yet.

Repro steps:
test/run_envoy_bazel_coverage.sh without setting test IP versions.

Test logs:

[ RUN      ] AddrFamilyAwareSocketOptionImplTest.V6EmptyOptionNames
test/common/network/addr_family_aware_socket_option_impl_test.cc:52: Failure
Actual function call count doesn't match EXPECT_CALL(os_sys_calls_, socket(_, _, _))...
         Expected: to be called once
           Actual: never called - unsatisfied and active
test/common/network/addr_family_aware_socket_option_impl_test.cc:53: Failure
Actual function call count doesn't match EXPECT_CALL(os_sys_calls_, close(_))...
         Expected: to be called once
           Actual: never called - unsatisfied and active
[  FAILED  ] AddrFamilyAwareSocketOptionImplTest.V6EmptyOptionNames (1 ms)