Surf object storage docs update.

[tvanerven]

What this PR does / why we need it:

Docs update for SURF object storage

Which issue(s) this PR closes:

Closes #10617

Special notes for your reviewer:

Suggestions on how to test this:

• I can show a working POC with these options if need be.

Does this PR introduce a user interface change? If mockups are available, please link/include them here:

• No

Is there a release notes update needed for this change?:

• Don't think so, I suspect SURF object store is an edge case for many implementers.

Additional documentation:

• No (just the PR)