refactor: only use qemu when building for arm

.github/actions/build-image/action.yml

@@ -18,9 +18,6 @@ runs:
         name: build
         path: build
 
-    - name: set up qemu
-      uses: docker/setup-qemu-action@v2
-
     - name: set up docker buildx
       id: buildx
       uses: docker/setup-buildx-action@v2
@@ -29,7 +26,6 @@ runs:
       shell: bash
       run: |
         docker buildx build \
-              --platform ${{ inputs.architecturet }} \
               --progress plain \
               --tag "dokku/dokku:latest" \
               .

.github/workflows/ci.yml

@@ -103,6 +103,9 @@ jobs:
     steps:
       - uses: actions/checkout@v3
 
+      - name: set up qemu
+        uses: docker/setup-qemu-action@v2
+
       - name: build-image
         uses: ./.github/actions/build-image
         with: