Restore Test - The test can perform backup and restore workflows

For testing the automated backups feature we will require an e2e test that validates the backups by ensuring the restore procedure works for a quorum loss disaster recovery scenario.

See the following doc for more background:
https://docs.google.com/document/d/1NkdOwo53mkNBCktV5tkUnbM4vi7bG4fO5rwMR0wGSw8/edit?usp=sharing

This story targets the milestone 2,3 and 4 of the restore test to ensure that the test has the ability to perform a backup and then restore from that backup in a disaster recovery scenario.

While the automated backups API is still in progress, the test will rely on the existing backup script to trigger a backup. Later on when we have a functional backup API behind a feature gate, the test can switch over to using that API to trigger backups.

We're starting with a basic crash-looping member restore first. The quorum loss scenario will be done in ETCD-423.