ignore RUSTSEC-2021-0124

This is a vulnerability in tokio, which is required by Actix-web. For
the moment, ignore it, and then decide whether to upgrade actix to suit,
or switch to a different (simpler) web server package.

.github/workflows/security.yml

@@ -15,6 +15,7 @@ jobs:
     name: "Audit Dependencies"
     steps:
       - uses: actions/checkout@v2
-      - uses: actions-rs/audit-check@v1
+      - uses: GothenburgBitFactory/audit-check@master
         with:
+          ignore: RUSTSEC-2021-0124
           token: ${{ secrets.GITHUB_TOKEN }}