optionally deploy Azure Sentinel solution into Tier 1 Log Analytics Workspace

[glennmusa]

Description

Adds an Azure Sentinel deployment to the Tier 1 Log Analytics Workspace by default.

Users can opt-out of this in two ways:

1. when invoking Terraform manually, supply a Terraform variable create_sentinel = false
2. or, when using the deploy.sh script, passing the --no-sentinel flag.

To demo this, deploy as you usually would: src/scripts/deploy.sh -s ${my_sub_id}

To deploy without Azure Sentinel: src/scripts/deploy.sh -s ${my_sub_id} --no-sentinel

Issue reference

The issue this PR will close: #256

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

[Breanna-Stryker]

Successful test in commercial, LGTM