The problem would manifest as this error message:

```
❌ Deployment failed: Error: Duplicate use of node id: 07a6878c7a2ec9b49ef3c0ece94cef1c2dd20fba34ca9650dfa6e7e00f2b9961:current_account-current_region-build
```

The problem was that we were using the full asset "destination identifier" for both the build and publish steps, but then were trying to use the `source` object to deduplicate build steps.

A more robust solution is to only use the asset identifier (excluding the destination identifier) for the build step, which includes all data necessary to deduplicate the asset. No need to look at the source at all anymore.

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