Adding .p12 file parser to Project-level Secure Files

What does this MR do and why?

This MR adds a Secure File Parser for .p12 files.

Context

• Original Issue: #374949 (closed)
• Original POC: !97548 (closed)
• First MR: !98586 (merged)
• Second MR: !99046 (merged)

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MR acceptance checklist

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