subgraph instance fails when challenge event is thrown.

[novaknole]

The problem:

Subgraph instance failed to run: Failed to process trigger in block #8117766 (cacdfd5cd0f8a1ace6d0fe41d5063ce4d32f80ecee7d26aeb238a4a78599a941), transaction 4b32577a9efe23a77704e7dcb54d90d8e0e3332b12fc28742e083114c08f5a87: Entity ContainerEventChallenge[0x3ec3929f0af90f2d66b5bc0286f87429ac659d411582babe9076684e30c49c60challenge0xf]: missing value for non-nullable field resolver wasm backtrace: 0: 0x225c - !generated/schema/ContainerEventChallenge#save 1: 0x22fc - !src/utils/events/handleContainerEventChallenge 2: 0x2462 - !src/GovernQueue/handleChallenged , code: SubgraphSyncingFailure, id:

The problem is ContainerEvent.save() for the Challenge event gets called before we set resolver on the object, which causes missing value for non-nullable field resolver.