Update MissingVerifier.java

dmn-verifier-app/src/main/java/de/unikoblenz/fgbks/dmn/core/verifier/MissingVerifier.java

@@ -29,7 +29,7 @@ public class MissingVerifier extends AbstractVerifier {
       for (Value[] missingInt : missingRules) {
         StringBuilder sb = new StringBuilder("In table ");
         sb.append(d.getName()); // TODO: add real name
-        sb.append(" the following rule is not defined: (");
+        sb.append(", the following rule is not defined: (");
         sb.append(
             Arrays.stream(missingInt)
                 .map(Value::getOrgExpression)