Only explicitly install dependencies for Scuba

[crutchfield]

🗣 Description

Change ScubaGear module to not automatically install dependencies. Checks if they are missing on import and advised user to use Initialize-SCuBA to add them.

closes #931

💭 Motivation and context

The import of Scuba caused dependencies to be checked/installed each time it is imported. This check took time (<2 minute) that impacts testing.

🧪 Testing

• Ran import of scuba with missing modules, verify warning
• Ran scuba with all module, verify no warning
• Ran scuba against tenant after import, verified expected results.
• Ran Smoke Test
• Nightly build is failing but is failing in main with same error.

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• PR targets the correct parent branch (e.g., main or release-name) for merge.
• Changes are limited to a single goal - eschew scope creep!
• Changes are sized such that they do not touch excessive number of files.
• All future TODOs are captured in issues, which are referenced in code comments.
• These code changes follow the ScubaGear content style guide.
• Related issues these changes resolve are linked preferably via closing keywords.
• All relevant type-of-change labels added.
• All relevant project fields are set.
• All relevant repo and/or project documentation updated to reflect these changes.
• Unit tests added/updated to cover PowerShell and Rego changes.
• Functional tests added/updated to cover PowerShell and Rego changes.
• All relevant functional tests passed.
• All automated checks (e.g., linting, static analysis, unit/smoke tests) passed.

✅ Pre-merge checklist

• PR passed smoke test check.

• Feature branch has been rebased against changes from parent branch, as needed

  Use Rebase branch button below or use this reference to rebase from the command line.

• Resolved all merge conflicts on branch

• Notified merge coordinator that PR is ready for merge via comment mention

✅ Post-merge checklist

• Feature branch deleted after merge to clean up repository.
• Verified that all checks pass on parent branch (e.g., main or release-name) after merge.

[buidav]

Quick line of feedback before I can test this out.
Update the README to match the new Initialize process.

[schrolla]

One small documentation change to help with clarity of usage. Change functions as expected and resolves the issue of running setup actions with each import well.

[buidav]

Approved with one minor suggestion fix for the README.

Also, we should include a section in the README for installing from PowerShell Gallery once the finishing touches are done with that.

[crutchfield]

@nanda-katikaneni PR ready to merge to main. Smoke test failure is for know g3 tenant issue.