[Backend] Fix issue refunding uncompleted payments

[jtapia]

Summary

• Remove Refund button for uncompleted payments
• Remove Credit button for payment on void and invalid state

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[jtapia]

In favor of #2932

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.69%. Comparing base (ca1ae4d) to head (7e914f7).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6094      +/-   ##
==========================================
- Coverage   92.42%   88.69%   -3.74%     
==========================================
  Files         389      829     +440     
  Lines        8005    17989    +9984     
==========================================
+ Hits         7399    15956    +8557     
- Misses        606     2033    +1427     

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[fthobe]

Hey @jtapia thank you for picking this up again after so much time. Could you also take a look at the coverage?