fix Use of a broken or weak cryptographic hashing (#7671)

Co-authored-by: lian <imwhatiam123@gmail.com>

thirdpart/registration/models.py

@@ -115,7 +115,10 @@ class RegistrationManager(models.Manager):
         username = user.username
         if isinstance(username, str):
             username = username.encode('utf-8')
-        activation_key = hashlib.sha1(salt+username).hexdigest()
+
+        # Take the first 16 character to avoid errors.
+        # (1406, "Data too long for column 'activation_key' at row 1")
+        activation_key = hashlib.sha256(salt+username).hexdigest()[:16]
         return self.create(emailuser_id=user.id,
                            activation_key=activation_key)