begin testing @grpc/grpc-js@0.6.9 as alternative to grpc

[bcoe]

@murgatroid99 believes he's continued to address some bugs in the @grpc/grpc-js libraries, based on logs we've been provided while debugging #770.

We're holding off on making this a recommendation for all users, as we don't want to continue to create disruptions, and the grpc transport is working well.

However, if a few folks would like to pilot the latest changes to @grpc/grpc-js, we would greatly appreciate the help).

The latest version is 0.6.9, after installing you should run npm ls, to make sure other dependencies have not pinned you on an older @grpc/grpc-js.

CC: @MichaelMarkieta, @Redgwell, @RaptDept, @xoraingroup

[Legogris]

@bcoe Motivation for closing this? 0.6.9 Unfurtunately does not work for us. Just discovered the thread in #770 now and will see if using grpc changes anything. Are there any known issues with 0.5.4? At least that seems to have been running fine for us on the publisher side.