Need to provide authenticated user to context in SignIn and SignUp mutation

This error can be reproduced if you request additional policy rules for the user when logging in

```suggestion
module Mutations
class SignIn < BaseMutation
argument :input, Types::SignInInput, required: true

type Types::Payloads::SignInPayload

def resolve(input:)
signin_user = SigninUser.call(input.to_h)

if signin_user.success?
context[:current_user] = result.user

signin_user
else
execution_error(error_data: signin_user.error_data)
end
end
end
end
```

co-authored @AnnaAleynik