Add shell script to allow for scaling of microk8s clusters

[addyess]

Summary

Creates a script using juju to scale microk8s to a specific number of nodes. This script creates 3 control-plane and 10 workers -- but could be better parameterized

Changes

None

Testing

This itself is a test. Used in a vsphere proxied environment as well as aws

Possible Regressions

None

Checklist

• Read the contributions page.
• Submitted the CLA form, if you are a first time contributor.
• The introduced changes are covered by unit and/or integration tests.