Enable go race detection for bazel tests.

There are a couple tests that need to run without race detection
enabled. See issue 39649 for details.

build/root/.bazelrc

@@ -17,3 +17,6 @@ build --sandbox_fake_username
 # TODO(ixdy): Remove this default once rules_go is bumped.
 # Ref kubernetes/kubernetes#52677
 build --incompatible_comprehension_variables_do_not_leak=false
+
+# Enable go race detection.
+test --features=race

pkg/master/BUILD

@@ -109,6 +109,7 @@ go_test(
         "master_openapi_test.go",
         "master_test.go",
     ],
+    features = ["-race"],
     library = ":go_default_library",
     deps = [
         "//pkg/api:go_default_library",

staging/src/k8s.io/client-go/tools/cache/BUILD

@@ -22,6 +22,7 @@ go_test(
         "store_test.go",
         "undelta_store_test.go",
     ],
+    features = ["-race"],
     library = ":go_default_library",
     deps = [
         "//vendor/github.com/google/gofuzz:go_default_library",