Add CI for Docker

.github/workflows/osrm-backend.yml

@@ -47,6 +47,16 @@ jobs:
         ./scripts/format.sh && ./scripts/error_on_dirty.sh
         node ./scripts/validate_changelog.js
         npm run docs && ./scripts/error_on_dirty.sh
+  
+  docker-image:
+    needs: format-taginfo-docs
+    runs-on: ubuntu-22.04
+    steps:       
+      - name: Check out the repo
+        uses: actions/checkout@v3
+      - name: Docker build
+        run: |
+          docker build -f docker/Dockerfile . 
 
   build-test-publish:
     needs: format-taginfo-docs

docker/Dockerfile

@@ -10,7 +10,8 @@ RUN apt-get update && \
 COPY . /src
 WORKDIR /src
 
-RUN NPROC=${BUILD_CONCURRENCY:-$(grep -c ^processor /proc/cpuinfo 2>/dev/null || 1)} echo "Building OSRM ${DOCKER_TAG}" && \
+RUN NPROC=${BUILD_CONCURRENCY:-$(grep -c ^processor /proc/cpuinfo 2>/dev/null || 1)} && \
+    echo "Building OSRM ${DOCKER_TAG}" && \
     git show --format="%H" | head -n1 > /opt/OSRM_GITSHA && \
     echo "Building OSRM gitsha $(cat /opt/OSRM_GITSHA)" && \
     mkdir -p build && \