Merge pull request #9876 from matt-kwong/filter-intern

Make portability tests pull images from Dockerhub and add test filter

tools/internal_ci/linux/grpc_portability_build_only.sh

@@ -35,4 +35,7 @@ cd $(dirname $0)/../../..
 
 git submodule update --init
 
+# download docker images from dockerhub
+export DOCKERHUB_ORGANIZATION=grpctesting
+
 tools/jenkins/run_jenkins_matrix.sh -f portability linux --build_only

tools/run_tests/python_utils/filter_pull_request_tests.py

@@ -98,6 +98,7 @@ _WHITELIST_DICT = {
   '^test/distrib/php/': [_PHP_TEST_SUITE],
   '^test/distrib/python/': [_PYTHON_TEST_SUITE],
   '^test/distrib/ruby/': [_RUBY_TEST_SUITE],
+  '^tools/internal_ci/': [],
   '^vsprojects/': [_WINDOWS_TEST_SUITE],
   'binding\.gyp$': [_NODE_TEST_SUITE],
   'composer\.json$': [_PHP_TEST_SUITE],