Resolve "Require the use of xarray v.0.13.0 instead of v.0.12.1"

What does this MR do?

This MR changes the xarray version requirement to v.0.13.0.

Can this MR be accepted?

• Increased xarray version requirement in the setup.py file from v.0.12.1 to v.0.13.0.
• Pipeline passes
• Changelog entry added
• Approved by @blsqr

Anything to double-check?

Related issues

Closes #97 (closed)