require regionmask >= 0.9

[mathause]

• Closes #xxx
• Tests added
• Passes isort . && black . && flake8
• Fully documented, including CHANGELOG.rst

Extracted requiring regionmask >= 0.9 from #398

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (9b0b76b) 87.90% compared to head (478238f) 87.95%.
Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #399      +/-   ##
==========================================
+ Coverage   87.90%   87.95%   +0.04%     
==========================================
  Files          40       40              
  Lines        1745     1743       -2     
==========================================
- Hits         1534     1533       -1     
+ Misses        211      210       -1     

Flag	Coverage Δ
unittests	87.95% <100.00%> (+0.04%)	⬆️

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[veni-vidi-vici-dormivi]

LGTM 😊

[mathause]

Thanks. Just for reference - support for regionmask 0.8 was broken as natural_earth_v5_0_0 is used (which is regionmask 0.9+)

mesmer/mesmer/core/mask.py

Line 56 in 3a6a9e1

land_110 = regionmask.defined_regions.natural_earth_v5_0_0.land_110