The ContextImplTest failed for me this afternoon:

test/common/ssl/context_impl_test.cc:93: Failure
Value of: 15 == context->daysUntilFirstCertExpires() || 14 == context->daysUntilFirstCertExpires()
Actual: false
Expected: true

It has been about a day since I last did a bazel clean, so it appears the problem is that the SSL certs are no longer expiring in the expected timeframe. I will fix this issue properly within the next few days. In the meantime, if you encounter this issue, just run "bazel clean" which will force regeneration of the SSL certs.