Handle case where resource version doesn't change after update #292
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The builtin APIs are full of edge cases where SMD and even the client-go scheme are not capable of comparing two versions of an API object. A few examples are documented in integration tests: resource quantities, fieldRefs, etc.
Eno currently uses a combination of SMD's equality logic and the scheme. But it turns out that the client-go scheme doesn't support defaulting - that requires importing a scheme for kubernetes/kubernetes, which is... not ideal.
So this PR proposes a different approach: keep updating until the resource version doesn't change. This essentially outsources the equality logic to apiserver: it compares the current/updated objects to determine if the write (and thus new resource version) is necessary.
Ideally synthesizers would set the relevant fields to avoid hitting this code. But IMO it's a better protection against tightloops than fully trusting Eno's comparison logic.