AO3-6564 Reduce fields where images are shown

[weeklies]

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• Have you added tests for any changed functionality?
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Issue

https://otwarchive.atlassian.net/browse/AO3-6564

Purpose

Strip images in the following:

• bookmarker notes
• pseud descriptions
• admin banners
• comments on news posts
• comment field on PAC and Support forms

Testing Instructions

See Jira issue.

Credit

weeklies (she/her)

[sarken]

Just a heads up this has merge conflicts!

[sarken]

Ohh, you know what just occurred to me: for news post comments, we should also be stripping the images from comment emails, both for the admin comment mailer and the user comment mailer.

Would you be up for making that change?

[weeklies]

Sorry @sarken, I don't think I'll have the time for a while.

[sarken]

No worries! Someone might push to your branch or open up a second PR with that change, though, since we'd like this for the next regular release after we update Ruby and Rails.