Make deployment securityContext configurable via values.yaml

[uluzox]

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Description

Add securityContext in values.yaml and templates to make it configurable in HelmRelease.

Motivation and Context

I use Kyverno to enforce security policies which I cannot comply to using your helm chart.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• [not applicable] I have added tests to cover my changes.
• [not applicable] All new and existing tests passed.

[CLAassistant]

All committers have signed the CLA.

[diemol]

Thank you!