fix(files): updateAll method

[maxschmi]

• Resolves: [Bug]: nxt 30.0.4 The "Update All" button to update all apps does not work properly if I am already logged in. #49866

Summary

There was a small error in the AppList.vue using this.update, but this is not a method of AppList, but of AppItem

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)

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[Pytal]

/compile

[skjnldsv]

cannot force push.
PR in #50078