flake: enable shellcheck pre-commit hook

Fix issue with not showing notification at 0% volume.

flake.nix

@@ -118,6 +118,10 @@
               nixpkgs-fmt = {
                 enable = true;
               };
+
+              shellcheck = {
+                enable = true;
+              };
             };
           };
         };

pkgs/change-audio/change-audio

@@ -9,7 +9,7 @@ else
 fi
 
 pamixer --allow-boost "$upDown" "$2"
-newVolume="$(pamixer --get-volume)"
+newVolume="$(pamixer --get-volume || true)"
 
 notify-send -u low \
     -h string:x-canonical-private-synchronous:change-audio \

pkgs/change-audio/default.nix

@@ -1,7 +1,7 @@
 { lib, libnotify, makeWrapper, pamixer, shellcheck, stdenvNoCC }:
 stdenvNoCC.mkDerivation rec {
   pname = "change-audio";
-  version = "0.1.0";
+  version = "0.1.1";
 
   src = ./change-audio;