`up` does not work when the user is in an org

[jkodroff]

Describe the bug

The call to pulumi_config.get_pulumi_user() should return the same value as pulumi org get-default. For example, my default org is an organization called jkodrofftest. When I run ./pulumi/python/runner -d -p aws -s try-kic-reference-architecture up, it fails with the following message:

Diagnostics:
  pulumi:pulumi:Stack (aws-eks-try-kic-reference-architecture):
    aws pulumi-iac-workshop profile
    error: update failed

  pulumi:pulumi:StackReference (jkodroff/aws-vpc/try-kic-reference-architecture):
    error: unknown stack "jkodroff/aws-vpc/try-kic-reference-architecture"

Note that the stack should be jkodrofftest/aws-vpc/try-kic-reference-architecture.

In order to fix, use the output of pulumi org get-default. (Working on finding the SDK call in Python. It exists in nodejs, so not sure why I can't find the Python version.)