Fix to_xarray_dataset merge error with conflicting values in coordinate

[BENR0]

Fixes the merge error Problem by allowing to pass the compat argument.

• Closes MergeError in to_xarray_dataset for Scenes containing data from seviri_l1b_nc reader #2179
• Tests added
• Fully documented

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.10%. Comparing base (38d106d) to head (43f8ce9).
Report is 275 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2827      +/-   ##
==========================================
- Coverage   96.10%   96.10%   -0.01%     
==========================================
  Files         381      381              
  Lines       55544    55559      +15     
==========================================
+ Hits        53383    53397      +14     
- Misses       2161     2162       +1     

Flag	Coverage Δ
behaviourtests	3.89% <4.34%> (-0.01%)	⬇️
unittests	96.20% <100.00%> (-0.01%)	⬇️

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[djhoese]

This looks good to me except the type annotation on compat which I've commented on inline. If that is resolved then this is good to merge.

[djhoese]

The failing test output really doesn't help determine what is wrong/unequal for that test.

[coveralls]

Pull Request Test Coverage Report for Build 12883477811

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.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 23 of 23 (100.0%) changed or added relevant lines in 2 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage remained the same at 96.214%

---

Files with Coverage Reduction	New Missed Lines	%
satpy/scene.py	1	92.25%

Totals
Change from base Build 12870674719:	0.0%
Covered Lines:	53643
Relevant Lines:	55754

---

💛 - Coveralls

[mraspaud]

@djhoese are you happy with this PR?