Update porter_stack_stefantest-graviton.yml

Author: stefanmcshane

.github/workflows/porter_stack_stefantest-graviton.yml

@@ -36,6 +36,4 @@ jobs:
         PORTER_TOKEN: ${{ secrets.PORTER_STACK_8_11 }}
         GH_TOKEN: ${{ github.token }}
         DOCKER_BUILDKIT: 1
-        PORTER_BUILDKIT_ARGS: --platform linux/arm64
-        PORTER_BUILDKIT_PUSH_ARGS: --platform linux/arm64