If you create a pull request and tick the "close branch" feature and then merge the branch. The resulting pipeline build will fail while attempting to clone the repo.
This is because the clone command explictly mentions the now deleted branch:
git clone --branch="feature/branch" ...
I can understand why it's being done... but it might be better to try and do the shallow clone of the branch, or if that fails do a full clone and checkout of the correct commit.