pubsub: parallelize integration tests

Two longest pubsub tests are TestAll and TestEndToEnd,
at 30 and 120 seconds respectively.
Running them in parallel saves about 30 seconds from
testing time.

It should not be possible for these tests to race,
since TestEndToEnd prefixes topics and subscriptions with
"endtoend-" string and TestAll does not.

Change-Id: Ifb4c4e50a5bf07551b4772ec55337aa82c8ef305
Reviewed-on: https://code-review.googlesource.com/13310
Reviewed-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
diff --git a/pubsub/endtoend_test.go b/pubsub/endtoend_test.go
index 1fd6c2b..f0d78e4 100644
--- a/pubsub/endtoend_test.go
+++ b/pubsub/endtoend_test.go
@@ -43,6 +43,7 @@
 // delivered to each subscription for the topic. It also tests that messages
 // are not unexpectedly redelivered.
 func TestEndToEnd(t *testing.T) {
+	t.Parallel()
 	if testing.Short() {
 		t.Skip("Integration tests skipped in short mode")
 	}
diff --git a/pubsub/integration_test.go b/pubsub/integration_test.go
index 4c5f68f..7b46e85 100644
--- a/pubsub/integration_test.go
+++ b/pubsub/integration_test.go
@@ -45,6 +45,7 @@
 }
 
 func TestAll(t *testing.T) {
+	t.Parallel()
 	if testing.Short() {
 		t.Skip("Integration tests skipped in short mode")
 	}