fix: Fix analyzer infos

[gspencergoog]

Description

This just fixes a number of analyzer info messages so that there aren't any in the repo. It cleans up the "Problems" view in VSCode, and actually could avoid some coding issues.

I looked at the CI, and it appears to already use dart analyze --fatal-infos, so I'm not sure why these were missed. Maybe because they haven't been modified since that was turned on?

There should be no change in functionality because of any of these changes, although the added awaits could cause a change in execution order.

Related Issues

No issues found for this.

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Breaking Change

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