test: updating ts integ test console output for readability

scripts/tile_server_integ.sh

@@ -101,6 +101,6 @@ if echo "$log_result" | grep -q "Success: 100.00%"; then
     exit 0
 else
     print_test_failed
-    echo "$log_result"
+    echo "$log_result" | sed -n '/^{.*"message":/p' | jq -r '.message' | sed 's/\\n/\n/g'
     exit 1
 fi