Update diego sync to not fetch every bit of every object, only completely fetch objects that need syncing

[Benjamintf1]

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Possible way to decrease cost of diego syncing? Have not investigated it fully to determine the effects of the change and whether it's actually more performant. Have not figured out how to remove the inner joins.

• An explanation of the use cases your change solves

Large envirnments may fetch all the process details of all the processes of the system rather then the information needed to preform a sync

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[philippthun]

Thanks, @Benjamintf1!

Fetching all the related stuff (e.g. apps, spaces, routes, service bindings) for all the unchanged processes seems to be really useless. I've checked the runtime of these queries on a large foundation; the queries themselves seem to be rather fast (i.e. 20 to 40ms each), but in the end this sums up to quite some useless query/busy time.

The inner joins come from here. This ensures that only processes having an associated droplet are fetched.