Merge pull request #3567 from jupyterhub/update-image-requirements

hub image: refreeze requirements.txt

Author: minrk

images/hub/requirements.txt

@@ -202,7 +202,7 @@ rfc3986-validator==0.1.1
     # via
     #   jsonschema
     #   jupyter-events
-rpds-py==0.20.0
+rpds-py==0.20.1
     # via
     #   jsonschema
     #   referencing

images/singleuser-sample/requirements.txt

@@ -254,7 +254,7 @@ rfc3986-validator==0.1.1
     # via
     #   jsonschema
     #   jupyter-events
-rpds-py==0.20.0
+rpds-py==0.20.1
     # via
     #   jsonschema
     #   referencing