Is your feature request related to a problem? Please describe.

There are number of issues already reported regarding the use of pkcs12 keys with ESO and how newer formats are not working with ESO. While many thinks that pkcs12 is a legacy format, many real application use the format to store certificates, including us.

Referenced issue:

• Working with pkcs12 is poorly documented #2281
• function "pkcs12cert" not defined #1666

The issue is due to the use of golang.org/x/crypto/pkcs12 not supporting more recent algorithms in pkcs12. (I am no security experts, so I am only summarizing from the referenced issues and solutions presented in these issues). Based on this issue: golang/go#30141 Golang team has frozen the development of golang.org/x/crypto/pkcs12 and recommended another Github fork. While the above issue did not specifically points to a fork, the only one I could find is software.sslmate.com/src/go-pkcs12`. The hashicorp go azure sdk made the same transition here: hashicorp/go-azure-sdk#328

Describe the solution you'd like
I would like to propose ESO transition the use of golang.org/x/crypto/pkcs12 to software.sslmate.com/src/go-pkcs12. The new lib is here: https://github.com/SSLMate/go-pkcs12

Describe alternatives you've considered
Not Applicable

Additional context

I am more than happy to do the work for this in the next a few days, but would like to open this issue in case there are any concerns.