Integrate the code for db to docs and enable autotests

Description

• Update documentation-building strategy
  • rely more on autodoc-ing
• Enable automated tests with pytest
  • Currently, only tests for atmospheric calibration and database are running
  • No tests on lstadapter included
  • Still need to decide on how to track the test files (regular git vs git-lfs)
• Tests are passing with warnings
  • Test job is allowed to fail
  • Failed tests are part of the atmospheric calibrations and need to be fixed
• Coverage badge is added (the proper badge production is to be tested)

Related Issue

How Has This Been Tested?

Test pipeline has been augmented

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.