Bump neutron gas price (#3096)

### Description

Updates the neutron gas price to be slightly above the min that was
recently updated :|
https://github.com/cosmos/chain-registry/blob/master/neutron/chain.json#L20

Deployed the Neutron relayer to include our recent changes that allow
for the gas price to be easily configured

### Drive-by changes

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Are there any minor or drive-by changes also included?
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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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rust/config/mainnet3_config.json

@@ -433,7 +433,7 @@
       "canonicalAsset": "untrn",
       "prefix": "neutron",
       "gasPrice": {
-        "amount": "0.5",
+        "amount": "0.57",
         "denom": "untrn"
       },
       "index": {

typescript/infra/config/environments/mainnet3/agent.ts

@@ -108,7 +108,7 @@ const neutron: RootAgentConfig = {
     rpcConsensusType: RpcConsensusType.Fallback,
     docker: {
       repo,
-      tag: '86b7f98-20231207-153805',
+      tag: '67585a2-20231220-223937',
     },
     gasPaymentEnforcement: [
       {