Make plutus version detection more robust

[nielstron]

Should address issue #426

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 88.71%. Comparing base (6e20135) to head (a9b296b).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
pycardano/backend/blockfrost.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #436      +/-   ##
==========================================
+ Coverage   85.14%   88.71%   +3.56%     
==========================================
  Files          32       33       +1     
  Lines        4679     4757      +78     
  Branches     1116     1136      +20     
==========================================
+ Hits         3984     4220     +236     
+ Misses        551      376     -175     
- Partials      144      161      +17     

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