Prevent mount point collision on validation

[yitsushi]

Describe the solution you'd like:
It is possible to set multiple volumes to be mounted to the same path. We can assume the end-user knows what they are doing, but should be a very straightforward validation.

Why do you want this feature:
To prevent unnecessary failures because of user error.

Anything else you would like to add:
Validate 2 things:

• Root volume mount point is /
• Do not allow multiple volumes to be mounted on the same path

Reference: #241 (comment)

[github-actions]

This issue is stale because it has been open 60 days with no activity.

[yitsushi]

This is still needed.

[Callisto13]

For now we are saying that any issues are user error and we dont care rn

[github-actions]

This issue is stale because it has been open 60 days with no activity.

[yitsushi]

Didn't we add check for that somewhere? Maybe @jmickey you know more.

[github-actions]

This issue was closed because it has been stalled for 365 days with no activity.