fix: search for email case-insensitively

Created by: Tirokk

Authored by roschaefer Oct 11, 2019 Merged Oct 14, 2019

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Pullrequest

Issues

• fix #1645 (closed)

Fun fact

The only uppercase email address that we have is: wegenVersuchterScriptInjectionBlockiert@roschaefer.de

So, a year ago, I updated this email address manually to stop a user from logging in again.