public void setCustomConverterId(String customConverterId) {
        this.customConverterId = customConverterId;
    }
Return true if is self referencing. Is considered self referencing where no other sources are specified,
i.e., no source properties or #CDATA in the xml def.

@return true if is self referencing
core/src/main/java/com/github/dozermapper/core/fieldmap/FieldMap.java