Document why to use a payloadless package for "Set Autofill Automatically"

[pboushy]

shell-intune-samples/macOS/Config/Set Autofill Automatically after PSSO Registration/README.md

Lines 22 to 24 in dc48d78

	## Deploying via Payloadless PKG in Intune
	A payloadless PKG is an empty package with no payload and no embedded scripts. The `Check-PSSO.zsh` script is added separately as a **pre-install script** when uploading the PKG to Intune.

Intune has capability to deploy scripts natively.
Please document why "Set Autofilly after PSSO" should be done via payloadless packages.