Add preamble for buildx

Signed-off-by: Orion Reblitz-Richardson <[email protected]>

Author: orionr

buildkite/test-template-ci.j2

@@ -469,6 +469,10 @@ steps:
         timeout_in_minutes: 600
         commands:
           - "aws ecr-public get-login-password --region us-east-1 | docker login --username AWS --password-stdin public.ecr.aws/q9t5s3a7"
+          - "aws ecr get-login-password --region us-east-1 | docker login --username AWS --password-stdin 936637512419.dkr.ecr.us-east-1.amazonaws.com"
+          - "docker buildx create --name vllm-builder --driver docker-container --use"
+          - "docker buildx inspect --bootstrap"
+          - "docker buildx ls"
           - |
             #!/bin/bash
             if [[ -z $(docker manifest inspect {{ docker_image_torch_nightly }}) ]]; then