[Documentation Update]: Add Getting Started with GitHub Copilot Section

[PlagueHO]

Check for previous/existing GitHub issues

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Description

As per discussion with @jtracey93 - adding a document to Usage Guide/Quickstart/Getting Started with GitHub Copilot and AVM

[microsoft-github-policy-service]

Important

The "Needs: Triage 🔍" label must be removed once the triage process is complete!

Tip

For additional guidance on how to triage this issue/PR, see the AVM Issue Triage documentation.

[matebarabas]

@PlagueHO, @jtracey93, do you have any updates on this? Is there anything the team or I can help with? Thanks!