Fixed agent deletion URL when accessed from subpages

[prathamalwayscomeslast]

Fixes #26003

Testing done

Manually tested agent deletion from subpages. Verified the delete action works correctly with no 404 errors

Screenshots (UI changes only)

Before

After

Proposed changelog entries

• Used urlPrefix for delete action so it works correctly

Proposed changelog category

/label bug

Proposed upgrade guidelines

N/A

Submitter checklist

• The issue, if it exists, is well-described.
• 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.
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Desired reviewers

@mention

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

Maintainer checklist

• There are at least two (2) approvals for the pull request and no outstanding requests for change.
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[prathamalwayscomeslast]

@MarkEWaite
I think this change is ready to be integrated

[prathamalwayscomeslast]

Taken care of in #26177