fix(appstore): Return an empty array in case of fail

[solracsf]

Fix #46552

Summary

If the fetch fail, $apps will be falsy.

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)

[nickvergessen]

Should have another log then in place?

[solracsf]

@nickvergessen log has been added.

[solracsf]

/backport to stable29

[solracsf]

/backport to stable28

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