CI: split tests.yml into stable tests and nightly tests

[Zeroto521]

handle 38-dev env fail https://github.com/Zeroto521/my-data-toolkit/runs/4101711375?check_suite_focus=true

[codecov]

Codecov Report

Merging #288 (390019f) into master (795cddb) will decrease coverage by 2.61%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #288      +/-   ##
==========================================
- Coverage   99.62%   97.01%   -2.62%     
==========================================
  Files          23       23              
  Lines         536      536              
  Branches       56       56              
==========================================
- Hits          534      520      -14     
- Misses          0       11      +11     
- Partials        2        5       +3     

Impacted Files	Coverage Δ
dtoolkit/accessor/_util.py	78.78% <0.00%> (-21.22%)	⬇️
dtoolkit/geoaccessor/geodataframe.py	91.30% <0.00%> (-8.70%)	⬇️
dtoolkit/geoaccessor/geoseries.py	94.11% <0.00%> (-5.89%)	⬇️
dtoolkit/accessor/dataframe.py	93.97% <0.00%> (-3.62%)	⬇️

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