feat(chart): update chart for v0.8.0

[stevehipwell]

What this PR does / why we need it:
This PR updates the Helm chart on the master branch in preparation to release it on the release-0.8 branch with a follow-up PR.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Related #1678

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[stevehipwell]

@dgrisonnet could you please take a look at this?

[stevehipwell]

@dgrisonnet I don't suppose you have time to look at this now? It'd be good to get a chart release out.

[dgrisonnet]

Sorry I missed your previous ping.

/lgtm
/approve

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dgrisonnet, stevehipwell

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