Use buildifier from nixpkgs

This avoids building the tool from scratch, if we can fetch it from the cache.

Author: avdv

BUILD.bazel

@@ -4,11 +4,13 @@ exports_files(["defs.bzl"])
 
 buildifier(
     name = "buildifier-diff",
+    buildifier = "@buildifier//:buildifier",
     diff_command = "diff -u",
     mode = "diff",
 )
 
 buildifier(
     name = "buildifier",
+    buildifier = "@buildifier//:buildifier",
     lint_mode = "warn",
 )

WORKSPACE

@@ -204,9 +204,14 @@ gazelle_dependencies()
 # Buildifier preamble
 #######################
 
-http_archive(
-    name = "com_github_bazelbuild_buildtools",
-    sha256 = "53119397bbce1cd7e4c590e117dcda343c2086199de62932106c80733526c261",
-    strip_prefix = "buildtools-8.2.1",
-    url = "https://github.com/bazelbuild/buildtools/archive/refs/tags/v8.2.1.tar.gz",
+nixpkgs_package(
+    name = "buildifier",
+    attribute_path = "buildifier",
+    build_file_content = """\
+filegroup(
+  name = "buildifier",
+  srcs = ["bin/buildifier"],
+  visibility = ["//visibility:public"]
+)""",
+    repository = "@nixpkgs",
 )