Optimistic locking for workspace-provider files

[thedadams]

Revisions were added to the workspace provider. Now we need to have an optional write option for "latest revision" that will fail with a conflict error if the passed revision is not the latest.

[thedadams]

The test for closing this issue should be closing this issue: #1813

The code was added specifically to address that issue.

[shweta8996]

Please provide me the additional steps to replicate this issue

[thedadams]

As long as the issue linked above is closed, then this can be closed.

[shweta8996]

As per the above comment, I marked as Done.