Add dialog when password reminder is active

[michaelschattgen]

We are receiving a lot of reports from people thinking that Aegis doesn't open biometrics unlock by default (ie #1159, #1155, #1151 and lots more). These users are unaware that this is caused by our password reminder encouraging them to enter their password. The password reminder doesn't tell the users that Aegis defaults back to biometrics unlock after entering their password once which is why we made #989.

This pull requests adds an additional dialog whenever a user clicks on the "biometrics" button below the password field when the password reminder is active as shown below:

The screenshot above shows old text. The new text is:

Biometric unlock by default
We occasionally prompt you to enter your password instead to ensure you haven't forgotten it and won't get locked out of your vault. After entering your password once, Aegis will default back to biometric unlock until it's time for another password reminder.

Please share your suggestions if you believe the text can be made clearer.

Closes #989