Add Erlang 28 to the github workflow

Drop 23

Author: tomas-abrahamsson

.github/workflows/main.yml

@@ -10,7 +10,7 @@ jobs:
 
     strategy:
       matrix:
-        otpvsn: [23, 24, 25, 26, 27]
+        otpvsn: [24, 25, 26, 27, 28]
       fail-fast: false
 
     container: