add --no-bastion to allow users to opt-out of Bastion host and Jumpbox creation

[glennmusa]

Description

This change proposes a --no-bastion flag to CLI deployments that allow a user to opt-out of deploying an Azure Bastion Host and Windows virtual machine jumpbox into the Hub network.

To try this out, add the --no-bastion flag to a deployment like:

src/scripts/deploy.sh -s {my_sub_id} --no-bastion

There is one known issue: as of this PR, users are not able to opt out of Bastion Host and Jumpbox deployments from the UI. This limitation is tracked here: #213 -- this was fixed with #218

Issue reference

The issue this PR will close: #189

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles or validates correctly
• BASH scripts have been validated using shellcheck
• All tests pass (manual and automated)
• The documentation is updated to cover any new or changed features
• Markdown files have been linted using the recommended linter. (See .vscode/extensions.json.)
• Relevant issues are linked to this PR

[brooke-hamilton]

I deployed with and without Bastion. 👍