Fix incorrect error message after successful password change (fixes #59723)

[aptiko]

• Resolves: Password change triggers password validation after saving #59723

Summary

This fix was written by Codex. I'm not a Vue developer. The logic of the one-line fix looks fine to me, although I don't understand the syntax details. When I tested manually it seemed to work.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI

[susnux]

tested and works.

[susnux]

@aptiko please adjust you commit to comply to conventional commits

e.g. fix(settings): do not validate empty password

[aptiko]

@susnux I did so.

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