[SYMSCAE]

This PR reverts the change that vendors libdiffpy. CI is expected to fail until a new libdiffpy release is availble in conda.

[SYMSCAE]

@sbillinge PR ready for review. But I'll mark it as draft for now until we have a new libdiffpy release.

[sbillinge]

@SYMSCAE this is still failing. It maybe just waiting for the upcoming release of libdiffpy? Please confirm and give an update on the progress there.

[SYMSCAE]

@SYMSCAE this is still failing. It maybe just waiting for the upcoming release of libdiffpy? Please confirm and give an update on the progress there.

The tests fail for different reasons. This PR test fails because we reverted back to use external libdiffpy and I've set this to expect 1.5.0+ (it will fail for 1.4.0 for another reason since function signature changed).

The other two tests fail because the commit hash and checksum mismatches (which could be caused by branch changes and we shouldn't bother further as we're not vendoring libdiffpy).