Remove deprecated authors field from pubspec.yaml

[sourcegraph-wk]

This PR removes the author field from any pubspec.yaml files in this repo,
as the field was deprecated in Dart 2.7 and is no longer needed.

Removing this field will silence the warning that pub publish emits, which
has the added benefit of allowing us to use pub publish --dry-run as a
quality check during CI.

If you'd like to retain the author information, we recommend adding an
AUTHORS.md file in the repo or the package directory.

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This PR was created automatically from a Sourcegraph batch change.
Please reach out to @evanweible-wf or #support-client-plat with any questions.

Created by Sourcegraph batch change Workiva/remove_pubspec_authors.

[aviary2-wf]

Security Insights

No security relevant content was detected by automated scans.

Action Items

• Review PR for security impact; comment "security review required" if needed or unsure
• Verify aviary.yaml coverage of security relevant code

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Questions or Comments? Reach out on Slack: #support-infosec.

[sydneyjodon-wk]

@Workiva/release-management-p

[rmconsole-wf]

+1 from RM