RAD-219 Update contributors file

[WilliamJamieson]

Resolves RAD-219

Closes #670

Update the contributors file with more detailed instructions for how to contribute to RAD.

Tasks

• Update or add relevant rad tests.
• Update relevant docstrings and / or docs/ page.
• Does this PR change any schema files?
  • Schema changes were discussed at RAD Review Board meeting.
• Does this PR change any API used downstream? (If not, label with no-changelog-entry-needed.)
  • Write news fragment(s) in changes/: echo "changed something" > changes/<PR#>.<changetype>.rst (see below for change types).
  • Start a romancal regression test (https://github.com/spacetelescope/RegressionTests/actions/workflows/romancal.yml) with this branch installed ("git+https://github.com/<fork>/rad@<branch>").
  • Update relevant roman_datamodels utilities and tests.

News fragment change types:

• changes/<PR#>.feature.rst: new feature
• changes/<PR#>.bugfix.rst: fixes an issue
• changes/<PR#>.doc.rst: documentation change
• changes/<PR#>.removal.rst: deprecation or removal of public API
• changes/<PR#>.misc.rst: infrastructure or miscellaneous change

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.99%. Comparing base (43416f7) to head (b4408d7).
⚠️ Report is 159 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #682   +/-   ##
=======================================
  Coverage   96.99%   96.99%           
=======================================
  Files           8        8           
  Lines         698      698           
=======================================
  Hits          677      677           
  Misses         21       21           

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[braingram]

Thanks for making this improvement. Just a few minor typos and one rewording.

[perrygreenfield]

A big improvement. Found one small typo.

[PaulHuwe]

This is a great start. I added a few fixes. I think we should add a small section directing people to the RTD (particularly for the helper script:
https://rad.readthedocs.io/en/latest/helper.html
and creating a schema:
https://rad.readthedocs.io/en/latest/creating.html)

[nden]

LGTM

[schlafly]

Thanks William, this looks good to me.

[nden]

@PaulHuwe It looks like all change requests were addressed. Do you mind a second review?

[PaulHuwe]

LGTM modulo one tweak