[rset] replace entity cw_rset on .limit(inplace=True) will avoid pb if the entity is still referenced by some other entity relations cache. Closes #2065643 Also, drop '_resultset' from some test names on the way (redundant information, we're in ResultSetTC...)

if repo.system_source.dbdriver == 'postgres':
    sql('ALTER TABLE appears ADD COLUMN weight float')
    sql('UPDATE appears SET weight=1.0 ')