[Users Management] Detach User from User Group in AWS Cognito

[MastalerzKamil]

Goal
Removing user from users group

Implementation plan

1. Create Construct for detaching user from Cognito group in authentication module
2. Create Lambda function for detaching user from group in AWS Cognito
3. Update schema by creating mutation that would create detach selected user from user group in Cognito
4. Connect mutation with Lambda as Data Source by creating resolver for mutation
5. Adding Unit tests