Add token for codecov to fix coverage upload (#7793)

Without the token, the new v4 action fails when uploading coverage from
the jobs in main. The PR actions don't need it and, in fact, github
should not pass the token to PRs coming from a fork.

.github/workflows/go-coverage.yml

@@ -9,7 +9,6 @@ on:
     paths-ignore:
     - 'release/**'
 
-
 jobs:
   build:
     runs-on: ubuntu-latest
@@ -26,3 +25,4 @@ jobs:
         uses: codecov/[email protected]
         with:
           files: ./coverage.txt
+          token: ${{ secrets.CODECOV_TOKEN }}