Issue with grant_to_oos_util.sql

Issue when running `grant_to_oos_util.sql username`


```
Error starting at line : 13 File @ /Users/vitoc/GitHub/oos-utils/install/grant_to_oos_utils.sql
In command -
grant execute on oos_util to &to_user
Error report -
ORA-00987: missing or invalid username(s)
00987. 00000 -  "missing or invalid username(s)"
*Cause:
*Action:
```