[FEATURE] Advanced email sending permission settings

[YoshihitoAso]

Is your feature request related to a problem? Please describe.

I would like to add the following functionality to the email sending function.

• Enable to control sending permission domains.
• Enable to set sending suppression emails. Enable to register emails to be suppressed using regular expressions.

Describe the solution you'd like

I would like to be able to configure the above settings using environment variables.