use build_tools ci image directly

.gitlab-ci.yml

@@ -37,18 +37,16 @@ build_and_deploy_layer:
   rules:
     - if: $CI_PIPELINE_SOURCE == "web"
   variables:
-    CI_ENABLE_CONTAINER_IMAGE_BUILDS: "true"
     ROLE_TO_ASSUME: arn:aws:iam::425362996713:role/sandbox-layer-deployer
     TARGET: 486234852809.dkr.ecr.us-east-1.amazonaws.com/ci/datadog-lambda-extension
   tags: ["arch:amd64"]
+  image: 486234852809.dkr.ecr.us-east-1.amazonaws.com/ci/datadog-lambda-extension
   artifacts:
     paths:
       - tmp/serverless/datadog_extension_signed.zip
   script:
     - mkdir tmp
     - git clone --branch ${AGENT_BRANCH} --depth=1 https://github.com/DataDog/datadog-agent.git
-    - dockerId=$(docker create --platform linux/amd64 ${TARGET})
-    - docker cp $dockerId:/build_tools .
     - EXTERNAL_ID=$(aws ssm get-parameter 
       --region us-east-1 
       --name ci.datadog-lambda-extension.externalid