Update elixir.yml

.github/workflows/elixir.yml

@@ -4,10 +4,10 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
-    - uses: actions/setup-elixir@v1.0.0
+    - uses: actions/checkout@v2
+    - uses: erlef/setup-elixir@v1
       with:
-        otp-version: 22.x
+        otp-version: 23.x
         elixir-version: 1.9.x
     - name: Dependencies
       run: |