Adjust logging level when selecting NetCDF backend

[pnuu]

This PR changes the logging level of NetCDF4 backend selection from INFO to DEBUG. It is unnecessary to print 80 times Trying reading nc file with netcdf4 engine… for an FCI scene.

• Closes #xxxx
• Tests added
• Fully documented
• Add your name to AUTHORS.md if not there already

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.34%. Comparing base (6c571f2) to head (58c10ca).
⚠️ Report is 77 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3372      +/-   ##
==========================================
- Coverage   96.35%   96.34%   -0.02%     
==========================================
  Files         466      466              
  Lines       59083    59083              
==========================================
- Hits        56931    56923       -8     
- Misses       2152     2160       +8     

Flag	Coverage Δ
behaviourtests	3.58% <0.00%> (ø)
unittests	96.43% <100.00%> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.