format: run buildifier on .bzl files. (#3824)

Risk Level: n/a
Testing: ./tools/check_format.py fix
Docs Changes: n/a
Release Notes: n/a

Signed-off-by: Piotr Sikora <piotrsikora@google.com>

Mirrored from https://github.com/envoyproxy/envoy @ df7a2918dbb71136018a1fdd92a0794b584afb3d

bazel/api_build_system.bzl

@@ -1,6 +1,6 @@
 load("@com_google_protobuf//:protobuf.bzl", "py_proto_library")
 load("@com_lyft_protoc_gen_validate//bazel:pgv_proto_library.bzl", "pgv_cc_proto_library")
-load("@io_bazel_rules_go//proto:def.bzl", "go_proto_library", "go_grpc_library")
+load("@io_bazel_rules_go//proto:def.bzl", "go_grpc_library", "go_proto_library")
 load("@io_bazel_rules_go//go:def.bzl", "go_test")
 
 _PY_SUFFIX = "_py"
@@ -18,7 +18,6 @@ def _LibrarySuffix(library_name, suffix):
         library_name += ":" + Label(library_name).name
     return _Suffix(library_name, suffix)
 
-
 # TODO(htuch): has_services is currently ignored but will in future support
 # gRPC stub generation.
 # TODO(htuch): Convert this to native py_proto_library once
@@ -54,7 +53,7 @@ def api_go_proto_library(name, proto, deps = []):
             "@com_github_golang_protobuf//ptypes/any:go_default_library",
             "@com_lyft_protoc_gen_validate//validate:go_default_library",
             "@googleapis//:rpc_status_go_proto",
-        ]
+        ],
     )
 
 def api_go_grpc_library(name, proto, deps = []):
@@ -71,7 +70,7 @@ def api_go_grpc_library(name, proto, deps = []):
             "@com_github_golang_protobuf//ptypes/any:go_default_library",
             "@com_lyft_protoc_gen_validate//validate:go_default_library",
             "@googleapis//:http_api_go_proto",
-        ]
+        ],
     )
 
 # This is api_proto_library plus some logic internal to //envoy/api.
@@ -84,7 +83,6 @@ def api_proto_library_internal(visibility = ["//visibility:private"], **kwargs):
 
     api_proto_library(visibility = visibility, **kwargs)
 
-
 # TODO(htuch): has_services is currently ignored but will in future support
 # gRPC stub generation.
 # TODO(htuch): Automatically generate go_proto_library and go_grpc_library
@@ -115,6 +113,7 @@ def api_proto_library(name, visibility = ["//visibility:private"], srcs = [], de
         ],
         visibility = visibility,
     )
+
     # Under the hood, this is just an extension of the Protobuf library's
     # bespoke cc_proto_library. It doesn't consume proto_library as a proto
     # provider. Hopefully one day we can move to a model where this target and