Osticket: [Feature Request] Add Google G Suite / Gmail OAuth Access

Prerequisites

• [ ] Can you reproduce the problem in a fresh installation of the "develop" branch?
  Yes

• [ ] Do you have any errors in the PHP error log, or javascript console?
  No

• [ ] Did you check the osTicket forums?
  Yes

• [ ] Did you perform a cursory search to see if your bug or enhancement is already reported?
  Yes

For more information on how to write a good bug report

Description

Google has announced they are disabling 'Less Secure Apps' which allow you to use G Suite accounts in OS Ticket via IMAP SSL and SMTP SSL for fetching tickets and sending replies to customers.

I tried disabling 'Less Secure Apps' in G Suite as recommended on the OS Ticket website, however Google blocks the login attempts from OS Ticket (even when it is strictly SSL), so the only way to keep it working is with Less Secure Apps enabled.

Are there any plans to add OAUTH access for G Suite / Gmail accounts? If not could we get a feature request setup for this?

Steps to Reproduce

1. Add Gmail email account to OS Ticket Settings >> Emails >> Update Email Address
2. Use imap.gmail.com + Port 993 for fetching and ssl://smtp.gmail.com + Port 465 for SMTP sending
3. Disable 'Less Secure Apps' in your Gmail / G Suite account

Expected behavior: Tickets should import properly and OS Ticket replies should be emailed to the customer

Actual behavior: Tickets do not import properly and replies are never emailed to the customer. In the Gmail account you receive a message:

Sign-in attempt was blocked
Someone just used your password to try to sign in to your account from a non-Google app. Google blocked them, but you should check what happened. Review your account activity to make sure no one else has access.

Versions

10.12.x
CentOS 7 latest, PHP 7.3