fix json decode error attribute name

[philnewm]

Fixes #7774

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• Commits are cleanly separated with meaningful messages (simple features and bug fixes should be squashed to one commit)
• A changelog entry or entries has been added for any significant changes
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See: Pull Request Walkthrough

[philnewm]

From reading through the logs it doesn't look like this is related to the change in this PR.
Could the failing test be caused by an external resource?

[dralley]

That particular test has been flaky recently, it's unrelated

[patchback]

Backport to 3.113: 💚 backport PR created

✅ Backport PR branch: patchback/backports/3.113/248a07be3f7e4ba2e6c5fbd4d467f16aeafbfb95/pr-7775

Backported as #7777

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