For issue 321 and 269

[MaceKuailv]

321 In snap method, sometimes the coords got a false time dimension.

269 Unpin matplotlib because cartopy update automatically solved the dependency bug.

[MaceKuailv]

There might be some test depends on the bug...I am a little reluctant to change the test.

[codecov[bot]]

Codecov Report

Merging #348 (77c0a4f) into main (3858c33) will decrease coverage by 0.01%. The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #348      +/-   ##
==========================================
- Coverage   94.75%   94.74%   -0.01%     
==========================================
  Files           9        9              
  Lines        3944     3940       -4     
  Branches      859      857       -2     
==========================================
- Hits         3737     3733       -4     
  Misses        131      131              
  Partials       76       76              

Flag	Coverage Δ
unittests	94.74% <100.00%> (-0.01%)	:arrow_down:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
oceanspy/subsample.py	97.69% <100.00%> (-0.02%)	:arrow_down:

:mega: We’re building smart automated test selection to slash your CI/CD build times. Learn more

[malmans2]

@MaceKuailv I would just delete code rather than commenting it out. If you did it on purpose, we use version control, so you don't have to worry too much about deleting code.