Remove deriving show

Author: benfaerber

.github/workflows/ci.yml

@@ -32,7 +32,6 @@ jobs:
         opam install . --deps-only --with-test --yes
         opam install bisect_ppx --yes
         opam install ppx_deriving --yes
-        opam install ppx_deriving_show --yes
 
     - name: Build
       run: opam exec -- dune build