Add result validation back to Docker scripts

.github/workflows/ci.yml

@@ -93,9 +93,15 @@ jobs:
             stain/jena-fuseki@sha256:4d84eb09dc69603cab990a25a5ad683cec648159f39ccf5dbffba312e7d7666a
           docker ps
       - name: insert data
-        run: node bin/fetch-sparql-endpoint.js http://127.0.0.1:8080/mydataset/update --query 'insert data { <ex:s> <ex:p> <ex:o> }'
+        run: |
+          node bin/fetch-sparql-endpoint.js http://127.0.0.1:8080/mydataset/update \
+            --query 'insert data { <ex:s> <ex:p> <ex:o> }' \
+          | grep 'OK' &> /dev/null && echo "OK" || (echo "Update failed" && exit 1)
       - name: test data existence
-        run: node bin/fetch-sparql-endpoint.js http://127.0.0.1:8080/mydataset/sparql --query 'select * where { ?s ?p ?o }'
+        run: |
+          node bin/fetch-sparql-endpoint.js http://127.0.0.1:8080/mydataset/sparql \
+            --query 'select * where { ?s ?p ?o }' \
+          | grep '{"s":"ex:s","p":"ex:p","o":"ex:o"}' &> /dev/null && echo "OK" || (echo "Query failed" && exit 1)
       - run: docker stop endpoint
         if: always()