container: update to fedora 35

As of the last week or so, fedora 35 is the oldest support fedora version.
This requires us to explicitly add python 3.9 packages to enable tox runs.

Signed-off-by: John Mulligan <[email protected]>

Author: phlogistonjohn

tests/container/Containerfile

@@ -1,4 +1,4 @@
-FROM fedora:34
+FROM fedora:35
 
 RUN yum install \
     -y --setopt=install_weak_deps=False \
@@ -12,6 +12,7 @@ RUN yum install \
     python3-samba \
     python3-wheel \
     python3-pyxattr \
+    python3.9 \
     samba-common-tools \
     && yum clean all \
     && true