publish on one elixir version only

Author: cleclefibanity

.github/workflows/publish_on_release.yml

@@ -10,7 +10,7 @@ jobs:
     strategy:
       matrix:
         otp: ['21.3.8.21']
-        elixir: ['1.8.2', '1.9.4', '1.10.4']
+        elixir: ['1.10.4']
     steps:
       - uses: actions/checkout@v2
       - uses: erlef/setup-elixir@v1