Pinning urllib to <2 (#1797)

Co-authored-by: Felix Sonntag <[email protected]>

Author: fsonntag

.github/workflows/build.bazel.sh

@@ -41,6 +41,7 @@ $PYTHON -m pip install --upgrade setuptools
 $PYTHON -m pip --version
 
 $PYTHON -m pip install -q ${TENSORFLOW_INSTALL}
+$PYTHON -m pip install -q "urllib3 <2"
 
 $PYTHON tools/build/configure.py