Error shows in Confirm Passphrase immediately when typing initial passphrase

### Steps to reproduce

1. Sign out of an account that hasn't exported its keys
2. Manually export keys and save the file on your device
3. In the Export room keys dialog, start typing out a passphrase

https://user-images.githubusercontent.com/20701752/174231888-7a176c7c-614c-46a0-b595-0c19f4f96e0b.mp4

### Outcome

#### What did you expect?

Confirm passphrase only shows its error state when I start typing in it or after I click export

#### What happened instead?

Confirm passphrase shows its error state immediately as I start typing in the first box

### Your phone model

Pixel 6 Pro

### Operating system version

Android 12

### Application version and app store

1.4.24-dev

### Homeserver

matrix.org

### Will you send logs?

No

### Are you willing to provide a PR?

Yes