feature/TMDM-7616 : Record delete success dialog should auto-hide after a few seconds
TMDM-7641: "Whole content fulltext search displays error"

Fixes incorrect query translation in case of full text search on a all entity fields.
Refactors UserQueryHelper::getFields to remove need for a metadata repository as argument.
Adapts unit tests following getFields() signature change.
(https://jira.talendforge.org/browse/TMDM-7641)
Misc: Don't perform validation tasks on system model (no need for validation).
Merge branch 'maintenance/5.6'