Run all bzl files through buildifier

Change-Id: I41c35ecef9037dfc8a00cbde2227e889be05ce1a
diff --git a/tools/bzl/plugin.bzl b/tools/bzl/plugin.bzl
index e2de4ed..f43ff91 100644
--- a/tools/bzl/plugin.bzl
+++ b/tools/bzl/plugin.bzl
@@ -10,6 +10,7 @@
 )
 
 PLUGIN_DEPS = ["//plugins:plugin-lib"]
+
 PLUGIN_DEPS_NEVERLINK = ["//plugins:plugin-lib-neverlink"]
 
 PLUGIN_TEST_DEPS = [