ci: bump chartpress version (that absorbs six workaround)

chartpress 1.1 includes a dependency on six, which helps binderhub not
need to handle the workaround that adding six was in the first place.

Author: consideRatio

.github/workflows/publish.yml

@@ -30,13 +30,7 @@ jobs:
         run: |
           . ./ci/common
           setup_helm v3.5.4
-          # FIXME: six is required by docker 5.0.0 but isn't explicitly required
-          #        any more.
-          #
-          #        Upstream issue:  https://github.com/docker/docker-py/issues/2807
-          #        Breaking commit: https://github.com/docker/docker-py/commit/c8fba210a222d4f7fde90da8f48db1e7faa637ec
-          #
-          pip install --no-cache-dir chartpress==1.0.* six pyyaml
+          pip install --no-cache-dir chartpress>=1.2 pyyaml
 
       - name: Setup push rights to jupyterhub/helm-chart
         # This was setup by...

dev-requirements.txt

@@ -1,5 +1,5 @@
 beautifulsoup4
-chartpress==1.0.*
+chartpress>=1.2
 click
 codecov
 html5lib
@@ -14,8 +14,3 @@ pytest-cov
 pyyaml
 requests
 ruamel.yaml>=0.15
-# FIXME: six is required by docker 5.0.0 but isn't explicitly required any more.
-#        Upstream issue:  https://github.com/docker/docker-py/issues/2807
-#        Breaking commit: https://github.com/docker/docker-py/commit/c8fba210a222d4f7fde90da8f48db1e7faa637ec
-#
-six