AO3-6608 Update delete icon checkbox text

[smclairecarden]

Pull Request Checklist

• [ x] Have you read "How to write the perfect pull request"?
• [x ] Have you read the contributing guidelines?
• [x ] Have you added tests for any changed functionality?
• [x ] Have you added the Jira issue number
  as the first thing in your pull request title (e.g. AO3-1234 Fix thing)
• [x ] Do you have fewer than 5 pull requests already open? If not, please wait
  until they are reviewed and merged before creating new pull requests.

Issue

https://otwarchive.atlassian.net/browse/AO3-6608

Delete icon alt and comment text when deleting icon. I forgot to update the checkbox text.

Purpose

What does this PR do?

Updates the checkbox text when deleting psued icons and alt text - Sorry this took so long!

Testing Instructions

How can the Archive's QA team verify that this is working as you intended?

If you have a Jira account with access, please update or comment on the issue
with any new or missing testing instructions instead.

See jira.

References

Are there other relevant issues/pull requests/mailing list discussions?

Credit

What name and pronouns should we use to credit you in the Archive of Our Own's Release Notes?

Claire C she/her.

If you have a Jira account, please include the same name in the "Full name"
field on your Jira profile, so we can assign you the issues you're working on.

Please note that if you do not fill in this section, we will use your GitHub account name and
they/them pronouns.