[POC] add csi driver installation options

[adel121]

What this PR does / why we need it:

This PR is just a POC in order to:

• Show an example of how custom CSI driver installation can be integrated to our existing public helm chart.
• Facilitate showing demos on how we can leverage custom CSI driver to overcome several challenges that we have.

Related Resources

• Datadog CSI driver POC implementation
• Datadog Cluster Agent custom diff to leverage CSI in admission controller

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• Chart Version bumped
• Documentation has been updated with helm-docs (run: .github/helm-docs.sh)
• CHANGELOG.md has been updated
• Variables are documented in the README.md
• For Datadog Operator chart or value changes update the test baselines (run: make update-test-baselines)