📧 Build J-Mail - Version 3

[robin-macpherson]

Description

There's a series of nice improvements that could be made to J-Mail that I do think are really important and, to be honest, I think would bring that particular feature to completion.

Tasks

• Improve the scale at which the system can operate at in terms of volume of notifications/content in an email
• Handle the issue where people like Linda seem to somewhat frequently receive two emails, the latter often being empty and only containing thanks info
• Improve styling so that notifications for a single post get bundled together more nicely - the title and image only need to be displayed once and then we can summarize the notifications underneath
• Set up C.I. for J-Mail with 🏗 Set up CI for j-mail #562
• Handle visual bug on Outlook with 📧 J-MAIL: Post Image Styling Wrong On Outlook #698
• Update Serverless verions and handle deprecation warnings with ⛔️ J-Mail / Serverless Deprecation Warnings  #589