Remove Plus users' manual removals' special-casing

[Vinnl]

References:

Jira: MNTOR-3172
Figma: https://www.figma.com/file/CaEKIhvSJqf6KNIMzSkt40/Concepts-for-Monitor-MVP-Redesign?type=design&node-id=11165-1860&mode=design&t=s1UG53aIWQeHAz2A-4

Description

Apparently we'll be sending them the same monthly activity emails
as Plus users who have not manually resolved anything.

Note that I also fixed a bug where I forgot to include the generic email styles with other emails than the monthly activity email with manual resolutions. (Ironically, I called out that I was afraid for forgetting that in the PR where I added the styles - only to do so in the very PR I called that out. "I suppose in practice people will start by copy-pasting an existing template" - except I didn't update that template 🙃 )

How to test

I left in the story with manual resolutions in Storybook, so you can compare that with the one without and see that they're the same.

Checklist (Definition of Done)

• Localization strings (if needed) have been added.
• Commits in this PR are minimal and have descriptive commit messages.
• I've added or updated the relevant sections in readme and/or code comments
• I've added a unit test to test for potential regressions of this bug.
• Product Owner accepted the User Story (demo of functionality completed) or waived the privilege.
• All acceptance criteria are met.
• Jira ticket has been updated (if needed) to match changes made during the development process.
• Jira ticket has been updated (if needed) with suggestions for QA when this PR is deployed to stage.