Update the code examples and tests scrips to point to the playground environment/localhost

[HWatanuki]

Describe the bug
The current code examples and test scripts could be pointing by default to the public playground cluster or localhost to facilitate experimentation by new users.

To Reproduce
Steps to reproduce the behavior:

1. Clone the repo
2. Intiate your python environment
3. cd to pyhpcc-internal\examples
4. Execute wu_regular.py
5. The following error message is displayed: 401 Client Error: Unauthorized for url

Expected behavior
By pointing to the public playground, the same code execution would successfully generate a workunit ID.

Screenshots
N/A

Desktop (please complete the following information):

• OS: Windows
• PyHPCC Version 0.1.0

Additional context
N/A