chore(deps): update codecov/codecov-action action to v3

Author: renovate-bot

.github/workflows/dart.yml

@@ -57,4 +57,4 @@ jobs:
       - name: Format coverage
         run: pub global run coverage:format_coverage --lcov --in=coverage.json --out=lcov.info --packages=.packages --report-on=lib
 
-      - uses: codecov/codecov-action@v2.1.0
+      - uses: codecov/codecov-action@v3.1.0