clan-cli: Add shellcheck as a runtimeDependencie

pkgs/clan-cli/default.nix

@@ -16,6 +16,7 @@
   classgen,
   pythonRuntime,
   templateDerivation,
+  shellcheck,
 }:
 let
   pyDeps = ps: [
@@ -51,6 +52,7 @@ let
   testDependencies = testRuntimeDependencies ++ [
     gnupg
     stdenv.cc # Compiler used for certain native extensions
+    shellcheck
     (pythonRuntime.withPackages pyTestDeps)
   ];