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-7693 : fix GWT Test case(IncrementalBuildTreeGWTTest, TreeDetailGWTTest) failed
TMDM-7847: "Model change checker report a "high" and "low"  impact when only set the role with write access"

Fix incorrect equals() in FieldMetadata implementations (was wrongly taking into account access writes).
Adds unit test to reproduce issue.
(https://jira.talendforge.org/browse/TMDM-7847)
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
Merge branch 'maintenance/5.6'