Bug fix: case-sensitive validation warning for filter granularity

[courtneyholcomb]

Description

Fixes a bad ValidationWarning. This warning was being triggered if you used lowercase granularity in a where filter, which should not be the case. This change makes it case insensitive.

Checklist

• [ ] I have read the contributing guide and understand what's expected of me
• [ ] I have signed the CLA
• [ ] This PR includes tests, or tests are not required/relevant for this PR
• [ ] I have run changie new to create a changelog entry