Wrapping Retry for Py3.10

The retrying_async library is not Python 3.10 ready, so we are providing
a 3.10 compatible callback for it to use instead of the default one

Change-Id: I15e9b64c70d4d294c9ff0c6c7048cd257f6e1b61
Signed-off-by: Mark Beierl <mark.beierl@canonical.com>