amp-cli: disable update check

amp tries to run an npm update but it fails due to /nix/store being
immutable.

pkgs/by-name/am/amp-cli/package.nix

@@ -66,7 +66,8 @@ buildNpmPackage (finalAttrs: {
 
   postInstall = ''
     wrapProgram $out/bin/amp \
-      --prefix PATH : ${lib.makeBinPath [ ripgrep ]}
+      --prefix PATH : ${lib.makeBinPath [ ripgrep ]} \
+      --set AMP_SKIP_UPDATE_CHECK 1
   '';
 
   passthru.updateScript = ./update.sh;