Updated sender email to existing "from-address" (#12044)

refs #12043

- On updating From-address from Members settings in Labs, we send a confirmation email to the updated address with magic link for verification
- Previously, no explicit sender email was being set for this so fallback config address was used
- This updates the sender address to use the current from address for "from-address" update emails

core/server/services/members/settings.js

@@ -17,6 +17,7 @@ function createSettingsInstance(config) {
                     logging.warn(message.text);
                 }
                 let msg = Object.assign({
+                    from: config.getEmailFromAddress(),
                     subject: 'Update email address',
                     forceTextContent: true
                 }, message);