Reverts "[Fuchsia] Use more high level fuchsia-gn-sdk templates (#55445)"

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Reverts: #55445

Initiated by: zijiehe-google-com

Reason for reverting: This change would break the build_fuchsia_artifacts.py without https://github.com/flutter/engine/pull/55832/files. I'd merge two into one.

Original PR Author: zijiehe-google-com

Reviewed By: {jrwang}

This change reverts the following previous change:
This change removes the in-house built pm-based build rules in favor of the high level fuchsia_component / fuchsia_package in the gn-sdk.

The build_fuchsia_artifacts.py is still using pm, and it will be handled in a following change.

Bug: http://b/353729557, http://b/368608542

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