Support teams that specify orgs other than GoogleCloudPlatform

[melinath]

For example, firebase uses a separate org on GitHub. This is expected to be a rare usecase.

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[modular-magician]

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[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

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[melinath]

Closing for now - not required. If we wanted to go this route we'd also need to add support for additional fine-grained service tokens with permissions to read each individual org's teams.