Merge pull request #160 from jplock/patch-1

Upgrade to graphql-java v12.0

Author: oliemansm

gradle.properties

@@ -1,5 +1,5 @@
 version = 7.3.4-SNAPSHOT
 group = com.graphql-java-kickstart
 
-LIB_GRAPHQL_JAVA_VER = 11.0
+LIB_GRAPHQL_JAVA_VER = 12.0
 LIB_JACKSON_VER = 2.9.8