TypeError: '<' not supported between instances of 'str' and 'int' when checking snapd version

[Michael Skalka]

Found during this test run: https://solutions.qa.canonical.com/qa/testRun/00e23a09-e2eb-4b09-ae41-41429c8f197f

On the prometheus charm. Full logs can be found in the `juju-crashdump-kubernetes` file in the `artifacts` link at the bottom of the test-run page.

From /var/log/juju/unit-prometheus-0.log:

2020-07-15 00:56:55 ERROR juju-log Hook error:
Traceback (most recent call last):
  File "/var/lib/juju/agents/unit-prometheus-0/.venv/lib/python3.6/site-packages/charms/reactive/__init__.py", line 73, in main
    hookenv._run_atstart()
  File "/var/lib/juju/agents/unit-prometheus-0/.venv/lib/python3.6/site-packages/charmhelpers/core/hookenv.py", line 1332, in _run_atstart
    callback(*args, **kwargs)
  File "/var/lib/juju/agents/unit-prometheus-0/charm/reactive/snap.py", line 294, in configure_snap_store_proxy
    ensure_snapd_min_version('2.30')
  File "/var/lib/juju/agents/unit-prometheus-0/charm/reactive/snap.py", line 259, in ensure_snapd_min_version
    if snapd_version < LooseVersion(min_version):
  File "/usr/lib/python3.6/distutils/version.py", line 52, in __lt__
    c = self._cmp(other)
  File "/usr/lib/python3.6/distutils/version.py", line 337, in _cmp
    if self.version < other.version:
TypeError: '<' not supported between instances of 'str' and 'int'

2020-07-15 00:56:55 DEBUG install Traceback (most recent call last):
2020-07-15 00:56:55 DEBUG install File "/var/lib/juju/agents/unit-prometheus-0/charm/hooks/install", line 22, in <module>
2020-07-15 00:56:55 DEBUG install main()
2020-07-15 00:56:55 DEBUG install File "/var/lib/juju/agents/unit-prometheus-0/.venv/lib/python3.6/site-packages/charms/reactive/__init__.py", line 73, in main
2020-07-15 00:56:55 DEBUG install hookenv._run_atstart()
2020-07-15 00:56:55 DEBUG install File "/var/lib/juju/agents/unit-prometheus-0/.venv/lib/python3.6/site-packages/charmhelpers/core/hookenv.py", line 1332, in _run_atstart
2020-07-15 00:56:55 DEBUG install callback(*args, **kwargs)
2020-07-15 00:56:55 DEBUG install File "/var/lib/juju/agents/unit-prometheus-0/charm/reactive/snap.py", line 294, in configure_snap_store_proxy
2020-07-15 00:56:55 DEBUG install ensure_snapd_min_version('2.30')
2020-07-15 00:56:55 DEBUG install File "/var/lib/juju/agents/unit-prometheus-0/charm/reactive/snap.py", line 259, in ensure_snapd_min_version
2020-07-15 00:56:55 DEBUG install if snapd_version < LooseVersion(min_version):
2020-07-15 00:56:55 DEBUG install File "/usr/lib/python3.6/distutils/version.py", line 52, in __lt__
2020-07-15 00:56:55 DEBUG install c = self._cmp(other)
2020-07-15 00:56:55 DEBUG install File "/usr/lib/python3.6/distutils/version.py", line 337, in _cmp
2020-07-15 00:56:55 DEBUG install if self.version < other.version:
2020-07-15 00:56:55 DEBUG install TypeError: '<' not supported between instances of 'str' and 'int'