Add notes for how to do shell integration with oh-my-posh

[zadjii-msft]

I was yesterday years old when I actually set up oh-my-posh for the first time. Sorry for being a persistent cmd user

[zadjii-msft]

@JanDeDobbeleer can you sanity check me?

[learn-build-service-prod]

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[JanDeDobbeleer]

can you sanity check me?

@zadjii-msft you should also be able to set shell_integration to true in the config which should do all that for you.