Added test for NCONC with INTO var duplacated in WITH clause.
Added test for NCONC with INTO var duplacated in WITH clause.

clasp-developers/SICL,clasp-developers/SICL,vtomole/SICL,vtomole/SICL,clasp-developers/SICL,clasp-developers/SICL,vtomole/SICL,vtomole/SICL