Missing securityContext attributes on container kube-rbac-proxy

[cthtrifork]

Description

Allows the following setup

kubeRbacProxy:
  securityContext:
    allowPrivilegeEscalation: false
    readOnlyRootFilesystem: true
    capabilities:
      drop:
      - all

Issues Resolved

Fixes #745

Check List

• [x] Commits are signed per the DCO using --signoff
• [ ] Unittest added for the new/changed functionality and all unit tests are successful
• [ ] Customer-visible features documented
• [ ] No linter warnings (make lint)

If CRDs are changed:

• [ ] CRD YAMLs updated (make manifests) and also copied into the helm chart
• [ ] Changes to CRDs documented

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