Changes to executeRelations

added EntityRef to the source_ref request property allOf list

added EntityRef to the target/main_entity_ref request property allOf list

the source_ref request property type changed from object to no type

the target/main_entity_ref request property type changed from object to no type

removed the request property source_ref/entity_id

removed the request property source_ref/entity_schema

removed the request property target/main_entity_ref/entity_id

removed the request property target/main_entity_ref/entity_schema