Added docker file and dockerhub publish action.

Signed-off-by: Dennis Labordus <dennis.labordus@alliander.com>

Author: Dennis Labordus

.github/workflows/dockerhub_publish.yml

@@ -32,4 +32,6 @@ jobs:
         uses: docker/build-push-action@v2
         with:
           push: true
-          tags: lfenergycompas/compas-open-scd:${GITHUB_REF##*/} lfenergycompas/compas-open-scd:latest
+          tags: |
+            lfenergycompas/compas-open-scd:${GITHUB_REF##*/}
+            lfenergycompas/compas-open-scd:latest