Add helm config parameter for "Shared Overhead"

[kbrwn]

What problem are you trying to solve?

There is no way to update shared overhead outside of /settings.html

Describe the solution you'd like

a "sharedOverhead" param in that can be set in the values.yaml

Describe alternatives you've considered

Updating the value via /getConfigs and /updateConfigByKey

How would users interact with this feature?

helm cmd line

gz#544

[dwbrown2]

@nikovacevic know you had a related PR here recently. This something that's on your radar?

[nikovacevic]

@dwbrown2 no, that was for shared tenancy costs (which, confusingly, some refer to by the name "shared overhead"). Happy to add this sometime soon, though, as it shouldn't take too long.