feat(infra): add limits for API and Iris in stage

[donghun1214]

Description

Stage 환경을 Production 환경과 동일시하기 위해 Stage 내 API 서버와 Iris 서버의 메모리, CPU 의 스펙을 제한하였습니다.

Additional context

API server hard limit 은 EC2 t3a.small 의 스펙으로 설정하였습니다.

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