Coin selection fix

[tacmota]

Fix coin selection bug for the test in this branch https://github.com/Python-Cardano/pycardano/tree/coin_selection_fix

The selector didn't initialize with the remaining amount before the selector function started.

[codecov]

Codecov Report

Attention: Patch coverage is 89.47368% with 4 lines in your changes missing coverage. Please review.

Project coverage is 88.75%. Comparing base (d250316) to head (793e861).
Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
pycardano/transaction.py	89.65%	0 Missing and 3 partials ⚠️
pycardano/txbuilder.py	80.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #445      +/-   ##
==========================================
- Coverage   88.80%   88.75%   -0.05%     
==========================================
  Files          33       33              
  Lines        4759     4792      +33     
  Branches      723      730       +7     
==========================================
+ Hits         4226     4253      +27     
- Misses        375      378       +3     
- Partials      158      161       +3     

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[cffls]

lgtm, thanks!