ci: increase tracer test suite memory request (#15324)

## Description

We were seeing some OOM Kills from k8s of the tracer test suite.

I saw memory usage spike to 3GB before being killed, this updates it to
4GB.

## Testing

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## Risks

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-->

## Additional Notes

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Author: brettlangdon

tests/suitespec.yml

@@ -251,6 +251,8 @@ suites:
   tracer:
     env:
       DD_TRACE_AGENT_URL: http://localhost:8126
+      KUBERNETES_MEMORY_REQUEST: "4Gi"
+      KUBERNETES_MEMORY_LIMIT: "4Gi"
     parallelism: 9
     paths:
       - '@tracing'