Async callback functions, partnership function, rsaes_oaep for KeyEncryptionAlgorithm

[chadgates]

Adding following features:

• Support for rsaes_oaep for decryption as well as encryption for keys as discussed here: KeyEncryptionAlgorithm #62 and making it available in partner
• Fixing merge issues for partnership functions as per Feature/partnership cb function #46
• Adding option to support async callback functions (I am working on django-pyas2 supporting async, so this would be required). Pytest update was required to support async tests.
• Adding option to define different signing algorithm for partners as discussed here: Other signing algorithms? #60

I am wondering if this should be last version to support python 3.7 and with next version we should upgrade python 3.8 - python 3.12? This also means, we have to upgrade some packages as well. Had to upgrade pytest for better async testing support.

[codecov]

Codecov Report

Attention: Patch coverage is 98.63014% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 96.78%. Comparing base (b9dc0a2) to head (cbf0659).
Report is 1 commits behind head on master.

Files	Patch %	Lines
pyas2lib/as2.py	97.72%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #65      +/-   ##
==========================================
+ Coverage   96.45%   96.78%   +0.32%     
==========================================
  Files           6        6              
  Lines         734      778      +44     
  Branches      131      147      +16     
==========================================
+ Hits          708      753      +45     
+ Misses         14       13       -1     
  Partials       12       12              

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[abhishek-ram]

can we split the changes into 3 PRs?

[chadgates]

Would be earliest in May. And was trying to avoid merge conflicts. Which order/separation would you like to get them?

[chadgates]

Closed to split into separate PR's