move kaniko build to a different file

.github/workflows/test-kaniko.yml

@@ -24,9 +24,8 @@ jobs:
           export GIT_PASSWORD="${{ secrets.GITHUB_TOKEN }}"
 
           # Build and push
-          /kaniko/executor --dockerfile="./images/ubi9.Dockerfile" \
+          /kaniko/executor --dockerfile="./images/kaniko-build-test.Dockerfile" \
             --context="${{ github.repositoryUrl }}#${{ github.ref }}#${{ github.sha }}" \
             --destination="ghcr.io/some-natalie/kubernoodles/kaniko-build:test" \
             --push-retry 5 \
-            --build-arg opts="TARGETPLATFORM=linux/amd64" \
             --image-name-with-digest-file /workspace/image-digest.txt

images/kaniko-build-test.Dockerfile

@@ -0,0 +1,10 @@
+FROM cgr.dev/chainguard/wolfi-base:latest
+
+# install some software
+RUN apk add --no-cache \
+  git \
+  jq \
+  wget
+
+# echo "hello world" on launch
+CMD ["echo", "hello world"]