A customer faced an issue when they face full disk. Mysql router configuration file was broken. As this charm doesn't handle whole configuration file, charm wrote just part of them based on template. so re-bootstrapping is needed when this symptom happens.
To do that, I put code to check configuration file size, and if it is under 1000bytes, run bootstrap.
func-test-pr: https://github.com/openstack-charmers/zaza-openstack-tests/pull/1196
Closes-Bug: #2004088
Change-Id: Ic28f0406eb8d5dbd9131ae83090498297ac48c31
d334665b2d