DirectPath have issues with CloudBuild

[singhravidutt]

DirectPath seems to have issues when connecting via cloudbuild. This got surfaced when DIrectpath fallback i.e. cloudpath, was disabled via TD (earlier TD was responding with cloudpath endpoint as a fallback too if directpath endpoint isn't working).
This got unnoticed till now due to fallback and surfaced once fallback was disabled.
Alternative to TD for directpath is gRPC-LB which seems to work with cloudBuild.