Update labeler version, fix yaml to work with v5 - #139564

This fixes #139511

• A bug has been fixed with sync-labels, meaning this needs to be a boolean now. Setting to true to match v4 logic.
• in labeler.yml, all labels must be a list of globs, so updated them all to be a list of any.
• Update the version to v5

This is a little annoying to test, since the way github actions works means that changes to workflows aren't run until after they are merged. A workaround is I forked these labeler changes to a new branch in my own repo and created a PR to merge to that branch, seen here: https://github.com/drewroengoogle/flutter/actions/runs/7102118110/job/19331743809?pr=2. Note the step Run actions/labeler@8558fd74291d67161a8a78ce36a881fa63b766a9 which ensures we are running on the latest labeler version in that check.

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• All existing and new tests are passing.

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