🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

.kokoro/docker/docs/Dockerfile

@@ -80,7 +80,6 @@ RUN wget -O /tmp/get-pip.py 'https://bootstrap.pypa.io/get-pip.py' \
 # Test pip
 RUN python3 -m pip
 
-
 # Install build requirements
 COPY requirements.txt /requirements.txt
 RUN python3 -m pip install --require-hashes -r requirements.txt

.kokoro/docker/docs/requirements.txt

@@ -1,5 +1,5 @@
 #
-# This file is autogenerated by pip-compile with Python 3.10
+# This file is autogenerated by pip-compile with Python 3.9
 # by the following command:
 #
 #    pip-compile --allow-unsafe --generate-hashes requirements.in