client-go: fix 'go build ./...'

Test-only directories seem to confuse go-build and make it fail. We do this as
a smoke test in the github publishing bot.

Kubernetes-commit: 48cba8a44f94d70cf2ff0ed4fb765c84da8519a6

discovery/fake/BUILD

@@ -3,6 +3,7 @@ package(default_visibility = ["//visibility:public"])
 load(
     "@io_bazel_rules_go//go:def.bzl",
     "go_library",
+    "go_test",
 )
 
 go_library(
@@ -30,9 +31,16 @@ filegroup(
 
 filegroup(
     name = "all-srcs",
-    srcs = [
-        ":package-srcs",
-        "//staging/src/k8s.io/client-go/discovery/fake/test:all-srcs",
-    ],
+    srcs = [":package-srcs"],
     tags = ["automanaged"],
 )
+
+go_test(
+    name = "go_default_xtest",
+    srcs = ["discovery_test.go"],
+    deps = [
+        "//vendor/k8s.io/apimachinery/pkg/version:go_default_library",
+        "//vendor/k8s.io/client-go/discovery/fake:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes/fake:go_default_library",
+    ],
+)

discovery/fake/discovery_test.go

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package fake
+package fake_test
 
 import (
 	"testing"

discovery/fake/test/BUILD

@@ -1,25 +0,0 @@
-load("@io_bazel_rules_go//go:def.bzl", "go_test")
-
-go_test(
-    name = "go_default_test",
-    srcs = ["discovery_test.go"],
-    deps = [
-        "//vendor/k8s.io/apimachinery/pkg/version:go_default_library",
-        "//vendor/k8s.io/client-go/discovery/fake:go_default_library",
-        "//vendor/k8s.io/client-go/kubernetes/fake:go_default_library",
-    ],
-)
-
-filegroup(
-    name = "package-srcs",
-    srcs = glob(["**"]),
-    tags = ["automanaged"],
-    visibility = ["//visibility:private"],
-)
-
-filegroup(
-    name = "all-srcs",
-    srcs = [":package-srcs"],
-    tags = ["automanaged"],
-    visibility = ["//visibility:public"],
-)