Venus,
They have not added that to their UI as something that can be configured. It is actually noted as an issue in the Beta 3 release notes. But you can work around this by manually editing the sql syntax in the config_Query,json.
Look for your "expr" attributes like this example:
"expr": "Crime_Type LIKE 'Drugs%'"
and adjust it to this:
"expr": "Upper(Crime_Type) LIKE Upper('Drugs%')"