add capability for M1 and M2 in MCMIP abi_l2_nc reader

[jlubbersgeo]

This is in reference to and solves the problems stated in #3062 by adding functionality to support MCMIP mesoscale files being loaded in using the abi_l2_nc reader.

The following test was run and confirms the files are loaded correctly:

import pyresample

import satpy
from satpy.scene import Scene
from satpy.utils import debug_on

print(f"satpy version: {satpy.__version__}")
print(f"pyresample version: {pyresample.__version__}")

debug_on()


file = [OR_ABI-L2-MCMIPM2-M6_G18_s20250431727563_e20250431728021_c20250431728094.nc"]

scn = Scene(filenames=file, reader="abi_l2_nc")
scn.load(["C01"])


print("\n", scn["C01"].attrs["scene_id"])

satpy version: 0.1.dev14471+gb6b4ef1.d20250212
pyresample version: 1.31.0

[DEBUG: 2025-02-12 10:03:39 : satpy.readers.yaml_reader] Reading ('C:\\Users\\jlubbers\\OneDrive - DOI\\Research\\Coding\\satpy\\satpy\\etc\\readers\\abi_l2_nc.yaml',)
[DEBUG: 2025-02-12 10:03:39 : satpy.readers.yaml_reader] Assigning to abi_l2_nc: ['C:\\Users\\jlubbers\\Desktop\\goes_test\\ops_test\\meso2\\OR_ABI-L2-MCMIPM2-M6_G18_s20250431727563_e20250431728021_c20250431728094.nc']
[DEBUG: 2025-02-12 10:03:39 : satpy.composites.config_loader] Looking for composites config file abi.yaml
[DEBUG: 2025-02-12 10:03:40 : pyorbital.tlefile] Path to the Pyorbital configuration (where e.g. platforms.txt is found): C:\Users\jlubbers\AppData\Local\mambaforge\envs\avogoes\Lib\site-packages\pyorbital\etc
[DEBUG: 2025-02-12 10:03:40 : satpy.composites.config_loader] Looking for composites config file visir.yaml
[DEBUG: 2025-02-12 10:03:40 : satpy.readers.abi_l2_nc] Reading in get_dataset CMI_C01.

 Mesoscale

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.11%. Comparing base (f7d5dba) to head (14c9f38).
Report is 6 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3063   +/-   ##
=======================================
  Coverage   96.11%   96.11%           
=======================================
  Files         383      383           
  Lines       55685    55685           
=======================================
  Hits        53523    53523           
  Misses       2162     2162           

Flag	Coverage Δ
behaviourtests	3.88% <ø> (ø)
unittests	96.21% <ø> (ø)

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[djhoese]

FYI @jlubbersgeo after this is merged, you'll need to force push the pytroll/satpy's main branch to get your main branch in sync. Otherwise any future PRs will be based off of this PR (your main branch) and it will be very confusing. In the future I would recommend creating a new git branch based off of main before making changes/commits. Let me know if you have any questions.

Thanks for fixing this!

[coveralls]

Pull Request Test Coverage Report for Build 13294118861

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
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• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall first build on main at 96.222%

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Totals
Change from base Build 13281916717:	96.2%
Covered Lines:	53770
Relevant Lines:	55881

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💛 - Coveralls