Wrong text regarding to password requirement

[eMKejTestingWarriors]

🐞 Describe the bug

The text, which we see, is "Must be at least 6 letters.", and should be "Must be at least 6 characters.", because it is implemented requirement.

🔥 How to reproduce

Steps to reproduce the behavior:

1. Go to Stendhal website.
2. Click on 'Join'.
3. Click on password input box.
4. Click outside it.
5. See the showed text.

🌍 Environment

• Web client

🛠️ Suggested fixes

Changing the text to "Must be at least 6 characters.

🔭 Additional information

[AntumDeluge]

"Letters" & "characters" are interchangeable in American English. But I do agree that "characters" sounds better.