Upgrade helm to 2.16.5

Previous release was 2.16.3. See release notes

• https://github.com/helm/helm/releases/tag/v2.16.5
• https://github.com/helm/helm/releases/tag/v2.16.4

and https://github.com/helm/helm/compare/v2.16.3...v2.16.5 for a full list of changes