Different email requirements in the java client and browser

[eMKejTestingWarriors]

🐞 Describe the bug

You can create an account with incorrect email format in java client but in browser it is impossible. Requirements should be consistent between browser and client.

🔥 How to reproduce

Steps to reproduce the behavior:

1. Try to create account with incorrect email format in browser, e.g. "aaaaa".
2. Try to create account with incorrect email format in java client.
3. There is no possibility in browser (an apropriate information is displayed). In client there is only warning displayed but still we can create account with wrong email.

🌍 Environment

• Java client
• Web client

🛠️ Suggested fixes

Unify requirements across the browser and client.

[AntumDeluge]

Java client is being outmoded & this may not qualify as being necessary to fix.