remove hack to suppress warnings about the git_repository() rule

Change-Id: Icb5fd8f9e785280d9d57e9ebf523db4efe31fef0
diff --git a/WORKSPACE b/WORKSPACE
index 671b958..8fd6f8d 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -78,6 +78,8 @@
 
 generate_gnmi()
 
+load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")
+
 git_repository(
     name = "build_bazel_rules_nodejs",
     remote = "https://github.com/bazelbuild/rules_nodejs.git",