Update project structure

[backmari]

Description of work:

In preparation for changing the autoreduction script and adding unit tests for its functions:

• update the repo structure to a more standard structure with src/ and tests/ at the top level
• make use of pytest fixtures tmp_path and template_dir to reduce the number of hard coded paths (there are some remaining hard coded paths that make the test fail unless run from inside the tests/ directory).

The plan is to have:

src/lr_reduction/
src/lr_autoreduction/
src/lr_livereduction/

However, all common functions should exist in src/lr_reduction/ and be imported from the python package lr_reduction.

Check all that apply:

• updated documentation
• Source added/refactored
• Added unit tests
• Added integration tests
• Verified that tests requiring the /SNS and /HFIR filesystems pass without fail

References:

• Links to IBM EWM items: Story 13227: [lr_reduction][WebMon] Add additional diagnostic plots to the output screen on monitor.
• Links to related issues or pull requests:

⚠️ Manual test for the reviewer

(Instructions for testing here)

Check list for the reviewer

• best software practices
  • 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

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.98%. Comparing base (f272935) to head (709858a).

Additional details and impacted files

@@             Coverage Diff             @@
##             next      #96       +/-   ##
===========================================
+ Coverage   87.30%   98.98%   +11.67%     
===========================================
  Files          25        8       -17     
  Lines        2883      591     -2292     
===========================================
- Hits         2517      585     -1932     
+ Misses        366        6      -360     

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[ktactac]

Reasonable structure changes and source changes to reflect that