Compatibility with graphql-java version 19.0

[luiznaac]

Description

When running a project using graphql-java on version 19.0, it fails due to a breaking change introduced on this latest release - graphql-java/graphql-java#2841

The error:

An attempt was made to call a method that does not exist. The attempt was made from the following location:

    graphql.kickstart.tools.directive.SchemaGeneratorDirectiveHelper.wireFields(SchemaGeneratorDirectiveHelper.java:159)

The following method did not exist:

    'graphql.com.google.common.collect.ImmutableList graphql.collect.ImmutableKit.map(java.lang.Iterable, java.util.function.Function)'

Also, the ImmutableKit class is annotated as @Internal, so maybe we shouldn't be handling with it directly.