Merge pull request #15077 from jtattermusch/fix_macos_interop_to_prod

Fix macos interop_to_prod tests

tools/internal_ci/helper_scripts/prepare_build_macos_interop_rc

@@ -33,9 +33,3 @@ git clone --recursive https://github.com/grpc/grpc-go ./../grpc-go
 git clone --recursive https://github.com/grpc/grpc-java ./../grpc-java
 git clone --recursive https://github.com/grpc/grpc-node ./../grpc-node
 git clone --recursive https://github.com/grpc/grpc-dart ./../grpc-dart
-
-# Set up Docker for Mac
-docker-machine create -d virtualbox --virtualbox-share-folder "/Users/kbuilder/workspace:" default
-docker-machine env default
-eval $(docker-machine env default)
-