Enable test for source plugins

Author: fendor

ghcide/test/exe/Main.hs

@@ -1212,7 +1212,6 @@ checkFileCompiles fp diag =
 pluginSimpleTests :: TestTree
 pluginSimpleTests =
   ignoreInWindowsForGHC810 $
-  ignoreForGHC92Plus "blocked on ghc-typelits-natnormalise" $
   testSessionWithExtraFiles "plugin-knownnat" "simple plugin" $ \dir -> do
     _ <- openDoc (dir </> "KnownNat.hs") "haskell"
     liftIO $ writeFile (dir</>"hie.yaml")