Build/Test Tools: Update codecov/codecov-action to 7.0.0.

This updates `codecov/codecov-action` from `v5.5.3` to `v7.0.0`, which includes a change in Keybase account being used by the action to one that Codecov is able to update going forward. Coverage reports are currently failing because of an inability to verify GPG signature integrity.

See #64893.

git-svn-id: https://develop.svn.wordpress.org/trunk@62496 602fd350-edb4-49c9-b593-d223f7449a82

Author: desrosj

.github/workflows/reusable-phpunit-tests-v3.yml

@@ -261,7 +261,7 @@ jobs:
 
       - name: Upload test coverage report to Codecov
         if: ${{ inputs.coverage-report }}
-        uses: codecov/codecov-action@1af58845a975a7985b0beb0cbe6fbbb71a41dbad # v5.5.3
+        uses: codecov/codecov-action@fb8b3582c8e4def4969c97caa2f19720cb33a72f # v7.0.0
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           files: wp-code-coverage${{ inputs.multisite && '-multisite' || '-single' }}-${{ github.sha }}.xml