[etcd-backup-restore]

Most notable changes

[USER] Added command-line options etcd-username and etcd-password to connect to etcd with username-password if necessary. (#170, @ae6rt)
[USER] Updated etcd vendoring version to 3.3.13. (#155, @shreyas-s-rao)
[USER] Full snapshot on etcd startup will now be deferred in favour of an initial delta snapshot, followed by a full snapshot and subsequent delta snapshots. (#154, @shreyas-s-rao)
[USER] Added functionality to trigger on-demand full snapshots via the HTTP endpoint /snapshot/full. (#143, @shreyas-s-rao)

[USER] All exposed metrics are initialised to zero values. (#180, @shreyas-s-rao)
[USER] In the case that initial delta snapshot fails, a full snapshot is tried instead. (#165, @shreyas-s-rao)
[USER] Fixed the sorting of snapshots. (#161, @swapnilgm)
[OPERATOR] Added new flag experimental-fail-below-revision flag for initializer and /initialization/start http call (#184, @swapnilgm)
[OPERATOR] The health status changes are now logged at INFO level to help debug issues with etcd readiness. (#182, @amshuman-kr)
[OPERATOR] Etcd-backup-restore now uses the go modules for its dependecy management. (#176, @kayrus)
[OPERATOR] Fixed liveness probe command in helm chart. (#172, @shreyas-s-rao)
[OPERATOR] Optimized WAL verification memory usage. (#155, @shreyas-s-rao)
[OPERATOR] Reduced etcd downtime by optimizing readiness probe. (#151, @shreyas-s-rao)
[OPERATOR] Updated the base image of alpine in docker container to 3.9.3. (#146, @swapnilgm)