Modified data file path

[dmitry-ganyushin]

Short description of the changes:

A data repo for reflectivity test is created. New path to find data is adjusted.

Long description of the changes:

Check list for the pull request

• [ x] I have read the [CONTRIBUTING]
• [ x] 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 -v

References

Story 4822