PyOpenSSL load_pkcs12 is deprecated

[chinodyt]

load_pkcs12 is deprecated, need to change to the following method adapt the rest of the code. Check;

• Ref 1

• Ref 2

• Source

• Change the loading method for PKCS12 certificates

• Update the PFX to PEM method

[chinodyt]

Changed PyOpenSSL package to cryptography (cryptography.io) package.