Update add_prs_and_issues_to_project.yml

now use migrated version of old project

Author: pchampin

.github/workflows/add_prs_and_issues_to_project.yml

@@ -15,5 +15,5 @@ jobs:
     steps:
       - uses: actions/add-to-project@v0.4.1
         with:
-          project-url: https://github.com/orgs/w3c/projects/82
+          project-url: https://github.com/orgs/w3c/projects/84
           github-token: ${{ secrets.ADD_TO_PROJECT_PAT }}