Fix RSQL filter in batch update query in assign target group

[strailov]

Refactor assignTargetGroupWithRsql to use a subquery-based approach
(WHERE id IN (SELECT id FROM ... WHERE <rsql_predicate>))
instead of applying the RSQL predicate directly to the CriteriaUpdate root.

The NOT EXISTS subquery generated by SpecificationBuilder.notEqualInLike for negated set attribute filters (tag!=, tag=out=) requires JOINs that do not work correctly when attached to an UPDATE root in EclipseLink's UpdateAllQuery. By wrapping the RSQL spec in a SELECT subquery, all JOINs and correlated subqueries execute in a proper SELECT context

Add integration test verifying tag!= filter works correctly
when assigning target groups via RSQL.

Old approach generated the following query :

UPDATE sp_target t
SET t.group_ = 'FilteredGroup'
WHERE NOT EXISTS (
    SELECT t2 FROM sp_target t2
    LEFT JOIN sp_target_tags tt ON t2.id = tt.target_id
    LEFT JOIN sp_tag tag ON tt.tag_id = tag.id
    WHERE t2.id = t.id AND tag.name = 'tag1'
)

Which fails in EclipseLink — t.id correlation in the subquery references the UPDATE root, which EclipseLink's UpdateAllQuery can't resolve properly for inherited @id fields.

New Approach :

UPDATE sp_target t
SET t.group_ = 'FilteredGroup'
WHERE t.id IN (
    SELECT t1.id FROM sp_target t1
    WHERE NOT EXISTS (
        SELECT t2 FROM sp_target t2
        LEFT JOIN sp_target_tags tt ON t2.id = tt.target_id
        LEFT JOIN sp_tag tag ON tt.tag_id = tag.id
        WHERE t2.id = t1.id AND tag.name = 'tag1'
    )
)

Also this approach did not work for hibernate, so when using hibernate the old approach is applied.
Meaniong : EclipseLink takes the subquery path (WHERE id IN (SELECT ...))to avoid UpdateAllQuery's @id resolution bug.
While Hibernate takes the direct predicate path for optimal single-statement execution.