Remove DueCredit

[eurunuela]

This PR closes#53.

Follow-up work of adding BibTex citations should happen in #46.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.26%. Comparing base (90ca567) to head (0a86057).
⚠️ Report is 30 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #54 +/- ##
==========================================
- Coverage 90.30% 90.26% -0.04% 
==========================================
Files 3 3 Lines 299 298 -1 ==========================================
- Hits 270 269 -1 
Misses 29 29 

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[tsalo]

LGTM. It looks like duecredit wasn't actually being used, so there are no specific citations to remove.

[eurunuela]

LGTM. It looks like duecredit wasn't actually being used, so there are no specific citations to remove.

That's right, but it was being imported by __init__.py, which is why I believe we could still see it when running tedana.