AO3-5846 Attempting to access a URL with an unsupported extension (e.g. json) results in a 500 error

[Cubostar]

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Issue

https://otwarchive.atlassian.net/browse/AO3-5846

Purpose

Redirects pages to 404 if they run into ActionView::MissingTemplate.

Testing Instructions

Go to a page such as https://test.archiveofourown.org/about.json, and you should be redirected to the 404 page instead of the 500 page.

Credit

Cubostar, he/him

[Cubostar]

When I tried to reproduce the bug, I only could reproduce the bug for home pages rendered with home_controller.rb. Putting the change in this file also appeared to fix the bug, but I figured that keeping it in application_controller.rb as suggested in the Jira ticket made more sense in case there are pages that I didn't find that have the bug.

[marcus8448]

Thanks!