Remove deprecated git clean strategy
What does this MR do?
Removes support for deprecated git clone strategy.
Why was this MR needed?
Please read #4175 (closed) for details
Are there points in the code the reviewer needs to double check?
Does this MR meet the acceptance criteria?
- Documentation created/updated
- Added tests for this feature/bug
In case of conflicts with
master- branch was rebased
What are the relevant issue numbers?
Closes #4175 (closed)