Update Powershell C&P: Use name instead of number to clarify Security Option

[James-Firth]

What and Why

This change allows for easier auditing by those not familiar with Powershell.

It replaces the -bor 3072 flag with [System.Net.SecurityProtocolType]::Tls12 which are equivalent. However, the TLS12 is both easier to read and for powershell newbies/non-programmers it's easier to find the documentation.

Info:

SecurityProtocolType name-to-number mapping. ie 3072 is equivalent to Tls12

Docs on SecurityPointManager

[James-Firth]

Bump/Any changes required for this? I could squash the commits if needed