Use serviceAccountTemplate from values

[mdsakalu]

serviceAccountTemplate was hardcoded as an empty object - this PR updates the cluster template to use the value specified in the chart values.

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[philippemnoel]

Thank you! 🙏 Good catch. CI is failing due to not having access to secrets, so will override.

[philippemnoel]

@mdsakalu Could you please sign the CLA? We need this in order to be able to merge your contribution.

[philippemnoel]

I'll open a separate PR and merge since the CLa isn't signed and tests don't run. Thank you 🙏

[philippemnoel]

See #64, thank you 🙏