[kube-prometheus-stack] Updating value name for nodeExporter MacOS dashboard

[nicon89]

What this PR does / why we need it

This PR adds new value - .Values.nodeExporterMacOS.enabled.
It's used for controlling creation of Node Exporter Mac OS Grafana dashboard.

Which issue this PR fixes

(optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged)
n/a

Special notes for your reviewer

Checklist

• [ X ] DCO signed
• [ X ] Chart Version bumped
• [ X ] Title of the PR starts with chart name (e.g. [prometheus-couchdb-exporter])

[QuentinBisson]

This looks more like a breaking change than a patch. What value does it bring exactly?

[nicon89]

It allows one to have just a dashboard for node-exporter, if one doesn't use MacOS node-exporters, so generally for as clean installation as possible. I basically wanted to disable dashboards that I will not use - this is one of them.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Any further update will cause the issue/pull request to no longer be considered stale. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Any further update will cause the issue/pull request to no longer be considered stale. Thank you for your contributions.

[nicon89]

Opened new pull request from new branch #3778