Fails to collect statistics from Redshift table with `super` typed column

**Describe the bug**
Piperider hits `function length(super) does not exist` error when trying to collect statistics from a table with a `super` typed column

**To Reproduce**
Steps to reproduce the behavior:
1. Make a DBT model that produces a column of type `super`
2. Tag it `piperider`
3. Run `piperider run`

**Expected behavior**
Success
