query51a - erroneous line break

Line 90 has an erronous line break causing the column alias to be on two lines.  Seems like an obvious mistake.

```sql
select v1.item_sk, v1.d_date, v1.web_sales, v1.store_sales, max(v2.web_sales) web_cumulative, max(v2.store_sales) s
tore_cumulative
```