custom:tenantId and custom:tenantTier not passed to new user

Assume I am a TenantAdmin signed-in in the Application App, and I create a new user in BASIC tier within the App, the Cognito attributes: custom:tenantId and custom:tenantTier are not set within the new user.

Later, if I login with the newly created user in the Application App, the products and orders cannot be retrieved. The ApiGatewayAuthorizer breaks as the custom:tenantId is not set in the user's parameters.

I suppose there is a bug in the user-management api? In my opinion it should be set in

server/src/layers/cognito/user_management_util.py

from this...
```python
def create_user(user_pool_id, user_details):
response = cognito.admin_create_user(
Username=user_details['userName'],
UserPoolId=user_pool_id,
ForceAliasCreation=True,
UserAttributes=
[
{
'Name': 'email',
'Value': user_details['userEmail']
},
{
'Name': 'email_verified',
'Value': 'true'
},
{
'Name': 'custom:userRole',
'Value': user_details['userRole']
}
]
)
return response
```

to this...
```python
def create_user(user_pool_id, user_details):
response = cognito.admin_create_user(
Username=user_details['userName'],
UserPoolId=user_pool_id,
ForceAliasCreation=True,
UserAttributes=
[
{
'Name': 'email',
'Value': user_details['userEmail']
},
{
'Name': 'email_verified',
'Value': 'true'
},
{
'Name': 'custom:userRole',
'Value': user_details['userRole']
},
{
'Name': 'custom:tenantId',
'Value': user_details['tenantId']
}
]
)
return response
```

Do you agree?

Start in server/src/layers/cognito/user_management_util.py at create_user, then trace how user_details supplies tenantId and tenantTier. Verify that newly created Cognito users receive the required tenant attributes and that a subsequent login can retrieve products and orders without the authorizer failure.

Written by the indexing model from the issue text.