add .toLowerCase to front end auth db query

[trillium]

Overview

The db allows users to use upper/lower case entries, which lets users create duplicate VRMS accounts jeff@example.com and Jeff@example.com.

This change transforms the email on the front end to be a lower case string, removing the potential casing problem.

Action items

• add .toLowerCase() to front end login call
• Merge PR into the feature branch: correct-db-casing