GitHub Actions: fix building of -debug release versions by fixing build-args syntax in workflow files

- master/latest was already fixed.

.github/workflows/tags.yaml

@@ -52,7 +52,9 @@ jobs:
       - name: Build and push amd64 Release Docker Image to DockerHub
         uses: docker/build-push-action@v2
         with:
-          build-args: DEBUG_BUILD=0,BASE_IMAGE_SUFFIX=
+          build-args: |
+            DEBUG_BUILD=0
+            BASE_IMAGE_SUFFIX=
           builder: ${{ steps.buildx.outputs.name }}
           context: .
           file: ./Dockerfile
@@ -65,7 +67,9 @@ jobs:
       - name: Build and push amd64 Debug Docker Image to DockerHub
         uses: docker/build-push-action@v2
         with:
-          build-args: DEBUG_BUILD=1,BASE_IMAGE_SUFFIX=-debug
+          build-args: |
+            DEBUG_BUILD=1
+            BASE_IMAGE_SUFFIX=-debug
           builder: ${{ steps.buildx.outputs.name }}
           context: .
           file: ./Dockerfile
@@ -80,7 +84,9 @@ jobs:
       - name: Build and push multiarch Release Docker Image to DockerHub
         uses: docker/build-push-action@v2
         with:
-          build-args: DEBUG_BUILD=0,BASE_IMAGE_SUFFIX=
+          build-args: |
+            DEBUG_BUILD=0
+            BASE_IMAGE_SUFFIX=
           builder: ${{ steps.buildx.outputs.name }}
           context: .
           file: ./Dockerfile
@@ -93,7 +99,9 @@ jobs:
       - name: Build and push multiarch Debug Docker Image to DockerHub
         uses: docker/build-push-action@v2
         with:
-          build-args: DEBUG_BUILD=1,BASE_IMAGE_SUFFIX=-debug
+          build-args: |
+            DEBUG_BUILD=1
+            BASE_IMAGE_SUFFIX=-debug
           builder: ${{ steps.buildx.outputs.name }}
           context: .
           file: ./Dockerfile

.github/workflows/test.yaml

@@ -40,7 +40,9 @@ jobs:
       - name: Build amd64 release image locally to Docker
         uses: docker/build-push-action@v2
         with:
-          build-args: DEBUG_BUILD=0,BASE_IMAGE_SUFFIX=
+          build-args: |
+            DEBUG_BUILD=0
+            BASE_IMAGE_SUFFIX=
           builder: ${{ steps.buildx.outputs.name }}
           context: .
           file: ./Dockerfile