chore(testutil): add testutil.GoleakOptions (#16070)

- Adds `testutil.GoleakOptions` and consolidates existing options to
this location
- Pre-emptively adds required ignore for this Dependabot PR to pass CI
https://github.com/coder/coder/pull/16066

coderd/notifications/dispatch/smtp_test.go

@@ -26,7 +26,7 @@ import (
 )
 
 func TestMain(m *testing.M) {
-	goleak.VerifyTestMain(m)
+	goleak.VerifyTestMain(m, testutil.GoleakOptions...)
 }
 
 func TestSMTP(t *testing.T) {

coderd/notifications/notifications_test.go

@@ -56,7 +56,7 @@ import (
 var updateGoldenFiles = flag.Bool("update", false, "Update golden files")
 
 func TestMain(m *testing.M) {
-	goleak.VerifyTestMain(m)
+	goleak.VerifyTestMain(m, testutil.GoleakOptions...)
 }
 
 // TestBasicNotificationRoundtrip enqueues a message to the store, waits for it to be acquired by a notifier,