Add interactive CLI to save user account

[frankharkins]

Summary

Closes #2054.

This PR adds an interactive command-line interface (CLI) that guides users through saving their account to disk. This should be easier for users as they can just run one command and be guided through the relevant choices, and it should be more secure as they're discouraged from storing their token in code they might share.

With qiskit-ibm-runtime installed, users will be able to run the following command to start the CLI.

qiskit-ibm-runtime save-account

This should also be compatible with pipx run, so users will be able to run pipx run qiskit-ibm-runtime save-account from any environment.

Examples

Here's a screenshot of me saving my account correctly.

Here's the output of --help:

(.venv) ~ $ qiskit-ibm-runtime --help      
usage: qiskit-ibm-runtime [-h] {save-account} ...

Scripts for the Qiskit IBM Runtime Python package

options:
  -h, --help      show this help message and exit

Scripts:
  This package supports the following scripts:

  {save-account}
    save-account  Interactive command-line interface to save your account locally.

Questions

What should I add to the documentation? I don't think it belongs in the API documentation in this repo as we don't want users to import these functions. Maybe we can add a note under QiskitRuntimeService.save_account recommending this instead? When released, we can update the guides.

[Eric-Arellano]

This is lovely!

[Eric-Arellano]

This looks great from my perspective!

[kt474]

Thanks @frankharkins, this looks great! I think for the documentation we should update the docstring in save_account and also add a release note explaining the purpose of the CLI and how to use it.

I was testing the tool and it works well with my IQP production accounts but it didn't seem to work for staging accounts - I'm guessing this is intended because external users won't have staging accounts?

I was also running into issues with trying to save a cloud account:

There may be an issue with how the cloud instances are returned.