'Save and send email' on global settings -> outbound mail does not save

Pressing the 'Save and send email' button on global settings -> outbound mail form, causes a page reload, and the expectation that settings have been saved, but changes are not saved.

To recreate:
1. Visit Global Settings >> Outbound Mail form
2. Change a value in the SMTP settings (e.g. the port number)
3. Click 'Save and send email' button
4. Click a navigation link away from this page (e.g. home page).
5. Return to Global Settings >> Outbound Mail form and observe previous values not reflecting the changes that were entered

Desired behaviour:

• save settings after clicking 'save and send email button'.
• possibly mirror the save button and redirect to the previous level in the menu after clicking save, but maybe useful to stay on that page for users who are trying multiple times to get setting right