Enable all tested-with GHC versions

Author: Gaël Deest

.github/workflows/main.yml

@@ -15,6 +15,10 @@ jobs:
         os: [ubuntu-latest]
         cabal: ["3.2"]
         ghc:
+          - "8.0.2"
+          - "8.2.2"
+          - "8.4.4"
+          - "8.6.5"
           - "8.8.4"
           - "8.10.2"
         # exclude: