feat: add redeem_product_voucher method

[Lucino772]

• add url for redeem_product_voucher method (same as check_product_voucher)
• add redeem_product_voucher method
• add tests for redeem_product_voucher method
• update README.md

[codecov-commenter]

Codecov Report

Merging #32 (114869a) into main (51fad20) will increase coverage by 0.38%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main      #32      +/-   ##
==========================================
+ Coverage   47.93%   48.31%   +0.38%     
==========================================
  Files          29       29              
  Lines         945      952       +7     
  Branches      119      120       +1     
==========================================
+ Hits          453      460       +7     
  Misses        479      479              
  Partials       13       13              

Impacted Files	Coverage Δ
mojang/api/session.py	92.77% <100.00%> (+0.66%)	⬆️

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