feat: Added simple function to mfdis.py

[camille12225]

New function returns 3 lists of integers for

1. Stress periods in the model
2. Timesteps in each stress period
3. Length of each timestep

[codecov]

Codecov Report

❌ Patch coverage is 9.09091% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 73.0%. Comparing base (96ede0d) to head (3c60197).
⚠️ Report is 465 commits behind head on develop.

Files with missing lines	Patch %	Lines
flopy/modflow/mfdis.py	9.0%	10 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##           develop   #2056     +/-   ##
=========================================
- Coverage     73.0%   73.0%   -0.1%     
=========================================
  Files          259     259             
  Lines        59298   57932   -1366     
=========================================
- Hits         43305   42294   -1011     
+ Misses       15993   15638    -355     

Files with missing lines	Coverage Δ
flopy/modflow/mfdis.py	89.1% <9.0%> (-2.8%)	⬇️

... and 72 files with indirect coverage changes

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[jdhughes-dev]

You will need to relint with black (see failed test). Also to maintain code coverage you need to add a small test of your function that confirms that you get expected results for a known case.

[camille12225]

Sure, I reformatted with black. I will push again when I add the CI test.

[wpbonelli]

it's probably best to return 0-based per flopy3+ convention

[wpbonelli]

@camille12225 develop has moved a lot and linting has switched to ruff since this was opened, in case you need to again it can be done with ruff check . and ruff format . from the project root. It looks like this PR doesn't need a rebase before merging though.