Format 'admin' differently in the setup wizard for clarity

[daniel-beck]

Followup to #9185 (comment): Make it clearer, through formatting, that "admin" is a username and not just referring to an administrator account.

If tentatively accepted, will update localizations (where possible, when unclear will delete)

Testing done

Ran this to take screenshots:

Proposed changelog entries

Too minor

Proposed upgrade guidelines

N/A

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1. The Jira issue, if it exists, is well-described.
2. The changelog entries and upgrade guidelines are appropriate for the audience affected by the change (users or developers, depending on the change) and are in the imperative mood (see examples). Fill in the Proposed upgrade guidelines section only if there are breaking changes or changes that may require extra steps from users during upgrade.
3. There is automated testing or an explanation as to why this change has no tests.
4. New public classes, fields, and methods are annotated with @Restricted or have @since TODO Javadocs, as appropriate.
5. New deprecations are annotated with @Deprecated(since = "TODO") or @Deprecated(forRemoval = true, since = "TODO"), if applicable.
6. New or substantially changed JavaScript is not defined inline and does not call eval to ease future introduction of Content Security Policy (CSP) directives (see documentation).
7. For dependency updates, there are links to external changelogs and, if possible, full differentials.
8. For new APIs and extension points, there is a link to at least one consumer.

Desired reviewers

@mention

Before the changes are marked as ready-for-merge:

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1. There are at least two (2) approvals for the pull request and no outstanding requests for change.
2. Conversations in the pull request are over, or it is explicit that a reviewer is not blocking the change.
3. Changelog entries in the pull request title and/or Proposed changelog entries are accurate, human-readable, and in the imperative mood.
4. Proper changelog labels are set so that the changelog can be generated automatically.
5. If the change needs additional upgrade steps from users, the upgrade-guide-needed label is set and there is a Proposed upgrade guidelines section in the pull request title (see example).
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[MarkEWaite]

This PR is now ready for merge. We will merge it after approximately 24 hours if there is no negative feedback.

/label ready-for-merge

[MarkEWaite]

I tested it and confirmed it looks right. I confirmed that the extra '{}' pair is needed in the hbs file otherwise the HTML formatting is not rendered correctly. Thanks!

[daniel-beck]

Removing merge label per

If tentatively accepted, will update localizations (where possible, when unclear will delete)

[github-actions]

Please take a moment and address the merge conflicts of your pull request. Thanks!

[github-actions]

Please take a moment and address the merge conflicts of your pull request. Thanks!

[github-actions]

Please take a moment and address the merge conflicts of your pull request. Thanks!