TMDM-7460 Can not save ReusableType fields which contains same sub-fields with sibling type
- Retreive field value by name for ReferenceFieldMetadata due to type change
https://jira.talendforge.org/browse/TMDM-7460
TMDM-7460: "Can not save ReusableType fields which contains same sub-fields with sibling type"

Amends proposed fix with a lookup by field name whatever implementation of FieldMetadata is found (more extensible in case of new implementation of FieldMetadata).
(https://jira.talendforge.org/browse/TMDM-7460)
Merge branch 'bugfix/TMDM-7460' into maintenance/5.6