Add new core tests to run_tests/run_python.sh

The tests don't currently get discovered by py.test due to their use of
the Python 2.7+ load_tests protocol.

tools/run_tests/run_python.sh

@@ -39,4 +39,12 @@ export LD_LIBRARY_PATH=$ROOT/libs/$CONFIG
 export DYLD_LIBRARY_PATH=$ROOT/libs/$CONFIG
 export PATH=$ROOT/bins/$CONFIG:$ROOT/bins/$CONFIG/protobuf:$PATH
 source "python"$PYVER"_virtual_environment"/bin/activate
+
+# TODO(atash): These tests don't currently run under py.test and thus don't
+# appear under the coverage report. Find a way to get these tests to work with
+# py.test (or find another tool or *something*) that's acceptable to the rest of
+# the team...
+"python"$PYVER -m grpc_test._core_over_links_base_interface_test
+"python"$PYVER -m grpc_test.framework.core._base_interface_test
+
 "python"$PYVER $GRPCIO_TEST/setup.py test -a "-n8 --cov=grpc --junitxml=./report.xml"