fix: use known registry commit in .registryrc (#4172)

### Description

Seems like the commit previously used is no longer part of a branch on
the repo and this is causing issues in the image CI, e.g.
https://github.com/hyperlane-xyz/hyperlane-monorepo/actions/runs/10040156538/job/27745616823#step:8:501

### Drive-by changes

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### Related issues

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- Fixes #[issue number here]
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### Backward compatibility

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implications, e.g. changes that would prohibit deploying older commits
using this infra tooling?

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### Testing

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.registryrc

@@ -1 +1 @@
-9bf371143538c157730216af630042d8f5aef560
+7c6bfefbaefb6aad19b114afb6743b1b70c69552