Key commits since the previous release:
ba8c216 upgrade client-go to 1.19.4
4378130 move from juju/errors to pkg/errors
be073e8 upgrade to go1.15.5
1a1b6f1 subnets: move forward the cursor to skip illegal subnet
8a1bcf6 Modify kube-flannel.yaml to use rbac.authorization.k8s.io/v1
c2d3069 preserve AccessKey & AccessKeySecret environment on sudo fix some typo in doc.
1850b09 iptables: handle errors that prevent rule deletes