Add azimuth angles for SEVIRI

[ninahakansson]

Save also azimuth angles to files for SEVIRI.

• Closes #xxxx
• Tests added
• Tests passed: Passes pytest level1c4pps
• Passes flake8
• Fully documented

[ninahakansson]

Thanks @yeigenbrodt for finding and fixing the issues!

[codecov]

Codecov Report

Attention: Patch coverage is 60.86957% with 9 lines in your changes are missing coverage. Please review.

Project coverage is 77.37%. Comparing base (2568eef) to head (2532e58).
Report is 3 commits behind head on main.

Files	Patch %	Lines
level1c4pps/seviri2pps_lib.py	25.00%	5 Missing and 4 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #80      +/-   ##
==========================================
- Coverage   77.61%   77.37%   -0.24%     
==========================================
  Files          21       21              
  Lines        1452     1472      +20     
  Branches      120      125       +5     
==========================================
+ Hits         1127     1139      +12     
- Misses        301      306       +5     
- Partials       24       27       +3     

Flag	Coverage Δ
unittests	77.37% <60.86%> (-0.24%)	⬇️

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[coveralls]

Pull Request Test Coverage Report for Build 8203062159

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

• 18 of 23 (78.26%) changed or added relevant lines in 2 files are covered.
• 9 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.2%) to 78.305%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
level1c4pps/seviri2pps_lib.py	7	12	58.33%

Files with Coverage Reduction	New Missed Lines	%
level1c4pps/metimage2pps_lib.py	1	0.0%
level1c4pps/seviri2pps_lib.py	3	77.48%
level1c4pps/init.py	5	85.17%

Totals
Change from base Build 6888794484:	-0.2%
Covered Lines:	1401
Relevant Lines:	1741

---

💛 - Coveralls