Support Elixir 1.18 in GitHub CI (#106)

Author: kianmeng

.github/workflows/ci.yml

@@ -16,11 +16,11 @@ jobs:
       matrix:
         include:
           - pair:
-              elixir: 1.11.3
-              otp: 21.3
+              elixir: "1.11"
+              otp: "21"
           - pair:
-              elixir: 1.17.2
-              otp: 27.0
+              elixir: "1.18"
+              otp: "27"
             lint: lint
     steps:
       - uses: actions/checkout@v4