potential fix for #753

[jacpete]

This a pull request for the fix suggested in and for issue #753.

I believe the following replacement for that section of code could fix both these issues. First, by changing the range function to uses toYaml instead when expanding the $securityContext mapping. And second, moving the mergeOverwrite line out of the .Job.container.supplementalGroupIds if statement and into the $securityContext if statement instead.

Noting that this may also be something that needs applied to other job.tpl files as well if approved. As an example:

helm/charts/rstudio-workbench/files/job.tpl

Lines 133 to 146 in c6c1b08

	{{- if .Job.container.supplementalGroupIds }}
	{{- $groupIds := list }}
	{{- range .Job.container.supplementalGroupIds }}
	{{- $groupIds = append $groupIds . }}
	{{- end }}
	{{- $_ := set $securityContext "supplementalGroups" (cat "[" ($groupIds | join ", ") "]") }}
	{{- $securityContext := mergeOverwrite $securityContext $templateData.pod.securityContext }}
	{{- end }}
	{{- if $securityContext }}
	securityContext:
	{{- range $key, $val := $securityContext }}
	{{ $key }}: {{ $val }}
	{{- end }}
	{{- end }}

[CLAassistant]

All committers have signed the CLA.

[lucasrod16]

Would you mind sharing some artifacts that verify the changes have been tested and work as expected? These changes are a bit trickier to test since this data is templated by the launcher at runtime and can't be easily validated with helm lint, helm template or unit tests.

Specifically, it would be helpful to see a launcher job successfully running with nested securityContext objects (e.g., appArmorProfile, seccompProfile).