[ENHANCEMENT] Verify 2FA after it's activated

**Describe the feature you'd like to have implemented**
I'd like to suggest that players should verify that they scanned 2FA codes by verifying it. So after they activate 2FA using
`/2fa enable , they should be prompted to enter the code that the Authenticator app gave them after scanning the QR code.

**Is your feature request related to an existing problem? Please describe.**
Players usually activate it & they don't know they need to scan the QR code & they just want it reset. There's also no `/2fa reset` command, like `/force2fareset` that would be useful, as well in this case.

**Additional context**
Almost any websites & applications prompt you to verify the 2FA after you scanned the code, otherwise do not activate it.