Cover password complexity validation with api tests

[vladyslavyarets]

Summary

Currently this functionality covered by integration tests but have but there is some bug (wrong HTTP status code and exception message sends from controller in exception path). Expected behavior: When password is weak the following json should be sended by the application:

{
  "response_code": 406,
  "error_message": "Password too weak"
}

Actual behavior:

{
  "response_code": 500,
  "error_message": "Unknown error. Please contact support."
}

This functionality will be hotfixed it task #451, but it still needed to be covered with Api tests.

Cover this and relative aspects with api testing

[vladyslavyarets]

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[vladyslavyarets]

task assigned by Artem Marchenko

[vladyslavyarets]

Done!