[prometheus-elasticsearch-exporter] Re-introduce pod security context toggle

[zeritti]

What this PR does / why we need it

This PR re-introduces a toggle on the pod security context (enabled by default) making thus life easier for OpenShift users.

Which issue this PR fixes

• fixes [prometheus-elasticsearch-exporter] podSecurityContext togglable for openshift compatibility #3532

Special notes for your reviewer

Checklist

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

[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.

[zanhsieh]

@monotek
Can you help with PR please?

[monotek]

why is this needed?
you could just comment out "podSecurityContext" and achive the same, or not?

[zeritti]

why is this needed? you could just comment out "podSecurityContext" and achive the same, or not?

Although the field can be set to null, using a toggle is preferred. Such a toggle had previously been present in the chart but unfortunately removed.

[monotek]

using a toggle is preferred

by whom?
i don't see the benefit.

i guess if it was removed before we might end up in a new pr by somebody else which removes it again.