Improvements to EtcdMachineSnapshot controller

[furkatgofurov7]

What this PR does / why we need it: Follow-up to https://github.com/rancher/turtles/pull/708#pullrequestreview-2277177404

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged): Fixes #

Special notes for your reviewer:

Checklist:

• [x] squashed commits into logical changes
• [ ] includes documentation
• [ ] adds unit tests
• [ ] adds or updates e2e tests