Fix broken singleton test

Summary: This test regularly fails on account of timing. Remove the timing upper bound.

Reviewed By: yfeldblum

Differential Revision: D33271470

fbshipit-source-id: 1369ef45bd49e500c35816bfdb21869f346b6f70

folly/test/SingletonTest.cpp

@@ -335,9 +335,7 @@ TEST(Singleton, SharedPtrUsage) {
     auto start_time = std::chrono::steady_clock::now();
     vault.destroyInstances();
     auto duration = std::chrono::steady_clock::now() - start_time;
-    EXPECT_TRUE(
-        duration > std::chrono::seconds{4} &&
-        duration < std::chrono::seconds{folly::kIsSanitizeAddress ? 30 : 6});
+    EXPECT_TRUE(duration > std::chrono::seconds{4});
   }
   EXPECT_EQ(vault.registeredSingletonCount(), 4);
   EXPECT_EQ(vault.livingSingletonCount(), 0);