Fix util method to check if variable is not null

[kashalls]

When the serverside middleware checks to see if any of the oauth providers are enabled, it checks to see if the config is not null.
In node, the nullish operator ? returns undefined instead of spewing a nasty error.

Config checks to see if it is not null.

> null === undefined
false

Fixes #457

[TacticalTechJay]

LGTM!