fix: Update action URL

Author: erikmd

.github/workflows/misc-test.yml

@@ -15,7 +15,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - run: id
-      - uses: erikmd/docker-coq-action@master
+      - uses: coq-community/docker-coq-action@v1
         with:
           opam_file: './coq-demo.opam'
           coq_version: 'latest'