update BUILD files

vendor/github.com/grpc-ecosystem/go-grpc-prometheus/BUILD

@@ -9,6 +9,7 @@ go_library(
         "server_reporter.go",
         "util.go",
     ],
+    importpath = "github.com/grpc-ecosystem/go-grpc-prometheus",
     visibility = ["//visibility:public"],
     deps = [
         "//vendor/github.com/prometheus/client_golang/prometheus:go_default_library",

vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/BUILD

@@ -17,6 +17,7 @@ go_library(
         "proto2_convert.go",
         "query.go",
     ],
+    importpath = "github.com/grpc-ecosystem/grpc-gateway/runtime",
     visibility = ["//visibility:public"],
     deps = [
         "//vendor/github.com/golang/protobuf/jsonpb:go_default_library",

vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/internal/BUILD

@@ -3,6 +3,7 @@ load("@io_bazel_rules_go//go:def.bzl", "go_library")
 go_library(
     name = "go_default_library",
     srcs = ["stream_chunk.pb.go"],
+    importpath = "github.com/grpc-ecosystem/grpc-gateway/runtime/internal",
     visibility = ["//visibility:public"],
     deps = ["//vendor/github.com/golang/protobuf/proto:go_default_library"],
 )

vendor/github.com/grpc-ecosystem/grpc-gateway/utilities/BUILD

@@ -7,6 +7,7 @@ go_library(
         "pattern.go",
         "trie.go",
     ],
+    importpath = "github.com/grpc-ecosystem/grpc-gateway/utilities",
     visibility = ["//visibility:public"],
 )