ci: test against latest elixir/otp (#13)

Author: grzuy

.github/workflows/ci.yml

@@ -11,8 +11,8 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - elixir_version: 1.18
-            otp_version: 27.2.4
+          - elixir_version: 1.19
+            otp_version: 28.1.1
             lint: true
           - elixir_version: 1.14
             otp_version: 25.3.2.18