valid_min_length is not working

[JoeriMeurisse]

Describe the bug
When running a scan on a SQL server dataset, using a valid_min_length definition on a column, the scan fails with an error message (see screenshot)

Context
relevant yaml piece under "columns:"

maiden_name:
valid_min_length: 3
tests:
- missing_percentage < 15
- invalid_percentage < 15

[albinkjellin]

This seems to be the case for Postgres as well.