Pytest, Existing GitLfs garnet-data repo connection and Code Coverage Initialization

[mpatrou]

Short description of the changes:

Updates in tests, pytest, codecoverage and garnet-data existing repository configurations

Long description of the changes:

• Failing tests are fixed
• Temporary directories from pytest used in every test
• Artifact organization
• mount_sns, mount_hfir and resources_intensive marker added.
• pytest --all runs all tests, pytest runs all test expet from resources_intensive
• CI for pytest and code coverage enabled
• existing gitlfs data repository: https://code.ornl.gov/sns-hfir-scse/infrastructure/test-data/garnet-data is connected to this one. The data repository was originally created for neutron garnet repository (front and back end), but it is not used. Existing marker, test and configurations taken from garnet repository

Check list for the pull request

• I have read the [CONTRIBUTING]
• I have read the [CODE_OF_CONDUCT]
• I have added tests for my changes
• I have updated the documentation accordingly

Check list for the reviewer

• I have read the [CONTRIBUTING]
• I have verified the proposed changes
• best software practices
  • all internal functions have an underbar, as is python standard
  • clearly named variables (better to be verbose in variable names)
  • code comments explaining the intent of code blocks
• All the tests are passing
• The documentation is up to date
• code comments added when explaining intent

Manual test for the reviewer

pytest --all : executes all tests
pytest: skips the resource intensive

hfir and sns mounts are necessary for some tests

References

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