feat: add taint & toleration to mainnet3 relayer node pool (#4780)

### Description

See
https://kubernetes.io/docs/concepts/scheduling-eviction/taint-and-toleration/

- In GKE, for the larger relayer node pool, added a taint: `NoSchedule`,
label `component=relayer`
- In our relayer workloads, they now have a toleration that matches that
taint
- As part of rollout, first did a NoExecute (evicting everything on the
big nodes), then moved to NoSchedule (so that some other pods like
daemonsets would still get onto these bigger nodes). I made sure the
hyperlane and neutron context relayers have these tolerations

### Drive-by changes

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Are there any minor or drive-by changes also included?
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### Related issues

- Fixes https://github.com/hyperlane-xyz/issues/issues/1309

### Backward compatibility

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

Yes/No
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### Testing

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What kind of testing have these changes undergone?

None/Manual/Unit Tests
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typescript/infra/src/agents/index.ts

@@ -164,6 +164,19 @@ export class RelayerHelmManager extends OmniscientAgentHelmManager {
       signer: signers[name],
     }));
 
+    if (!values.tolerations) {
+      values.tolerations = [];
+    }
+
+    // Relayer pods should only be scheduled on nodes with the component label set to relayer.
+    // NoSchedule was chosen so that some daemonsets (like the prometheus node exporter) would not be evicted.
+    values.tolerations.push({
+      key: 'component',
+      operator: 'Equal',
+      value: 'relayer',
+      effect: 'NoSchedule',
+    });
+
     return values;
   }
 }

typescript/infra/src/config/agent/agent.ts

@@ -36,6 +36,7 @@ export interface HelmRootAgentValues {
   image: HelmImageValues;
   hyperlane: HelmHyperlaneValues;
   nameOverride?: string;
+  tolerations?: KubernetesToleration[];
 }
 
 // See rust/main/helm/values.yaml for the full list of options and their defaults.
@@ -132,6 +133,13 @@ export interface KubernetesComputeResources {
   memory: string;
 }
 
+export interface KubernetesToleration {
+  key: string;
+  operator: string;
+  value: string;
+  effect: string;
+}
+
 export class RootAgentConfigHelper implements AgentContextConfig {
   readonly rawConfig: RootAgentConfig;