Allow configuring enablePlatformTags via plugins

[eifinger]

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Fixes #3518🛠️

This PR tries to pick up https://github.com/GoogleContainerTools/jib/pull/3710 I added the requested integration test testSteps_forBuildToDockerRegistry_multiplePlatforms

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[eifinger]

Is there anything I can do to get the conversation started?

[msvticket]

Maybe this is something you could look at @mpeddada1 ?

[cholmes-axoni]

Is their any update or status of this MR?