Save custom values in settings to be used anywhere

If integrating with different services via workflows, good to have a list of custom variables saved somewhere in the settings. Can reuse the custom value, e.g., {{metaPixel}}, {{anotherApiKey}} in the workflow, e.g., code action. This way, we get ability to only allow admins to set the variables and other users can simply still use the workflow without knowing the actual value of the variable.