Fix //third_party/quic/core:quic_connection_test with randomized flags
One test does not set/check all involved flags and so fails when flags are flipped randomly, which is a new build mode we are introducing:
```
blaze test //third_party/quic/core:quic_connection_test \
--test_arg=--gfe2_invert_all_feature_flags_for_test=true \
--test_arg=--gfe2_feature_flags_randomize_for_test=random
```
Passes with the fix: http://sponge2/14c9e09d-c2cf-4166-82dc-95f2b6e3edac
PiperOrigin-RevId: 334141583
Change-Id: Id7bd2572a87f2937d397d0eaa95f23a106147bac
1 file changed