Different key funder job name (#3506)

### Description

- My changes in #3491 / #3492 were kind of accurate - according to
prometheus/pushgateway#65 even using pushAdd
will displace existing metrics. It's all very confusing!
- I tested this with a script that pushed some test metrics to the push
gateway - basically by having the key funder use a different job name
than the mainnet2 one, the metrics each of them push won't conflict with
one another

### 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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typescript/infra/config/environments/mainnet3/funding.ts

@@ -9,7 +9,7 @@ import { environment } from './chains';
 export const keyFunderConfig: KeyFunderConfig = {
   docker: {
     repo: 'gcr.io/abacus-labs-dev/hyperlane-monorepo',
-    tag: '7781bce-20240326-173938',
+    tag: 'd94cc52-20240328-104504',
   },
   // We're currently using the same deployer/key funder key as mainnet2.
   // To minimize nonce clobbering we offset the key funder cron

typescript/infra/scripts/funding/fund-keys-from-deployer.ts

@@ -238,7 +238,7 @@ async function main() {
     failureOccurred ||= await funder.fund();
   }
 
-  await submitMetrics(metricsRegister, 'key-funder');
+  await submitMetrics(metricsRegister, `key-funder-${environment}`);
 
   if (failureOccurred) {
     logger.error('At least one failure occurred when funding');