1. Proposed title of this feature request

Allow for an alias with pkcs12 keystore
2. What is the nature and description of the request?

Currently, there's no way to configure an alias with a pkcs12 keystore.  This is available to jks. I found some notes on this on the upstream project

https://github.com/cert-manager/cert-manager/issues/7066

https://github.com/cert-manager/go-pkcs12/pull/1

oc explain certificate.spec.keystores.jks
GROUP:      cert-manager.io
KIND:       Certificate
VERSION:    v1

FIELD: jks <Object>


DESCRIPTION:
    JKS configures options for storing a JKS keystore in the
    `spec.secretName` Secret resource.
    
FIELDS:
  alias    <string>
    Alias specifies the alias of the key in the keystore, required by the JKS
    format.
    If not provided, the default alias `certificate` will be used. 

3. Why does the customer need this? (List the business requirements here)

They have a multiple applications that use this alias field to find the proper certificate.

4. List any affected packages or components.

cert manager