Use a larger sleep time in get_allocation_profile_rpc_test so that the test doesn't flake on Windows

runtime/observatory/tests/service/get_allocation_profile_rpc_test.dart

Index: runtime/observatory/tests/service/get_allocation_profile_rpc_test.dart
diff --git a/runtime/observatory/tests/service/get_allocation_profile_rpc_test.dart b/runtime/observatory/tests/service/get_allocation_profile_rpc_test.dart
index 2af7ffec62c90e14b27c340a3f33d7cfbace069a..6d7b8fd45e520143156770a3b7efa4f7f7d8bdff 100644
--- a/runtime/observatory/tests/service/get_allocation_profile_rpc_test.dart
+++ b/runtime/observatory/tests/service/get_allocation_profile_rpc_test.dart
@@ -46,7 +46,7 @@ var tests = [
     expect(result['members'].length, isPositive);
     expect(result['members'][0]['type'], equals('ClassHeapStats'));
 
-    await sleep(10);
+    await sleep(1000);
 
     result = await isolate.invokeRpcNoUpgrade('_getAllocationProfile', params);
     var secondReset = result['dateLastAccumulatorReset'];
@@ -67,7 +67,7 @@ var tests = [
     expect(result['members'].length, isPositive);
     expect(result['members'][0]['type'], equals('ClassHeapStats'));
 
-    await sleep(10);
+    await sleep(1000);
 
     result = await isolate.invokeRpcNoUpgrade('_getAllocationProfile', params);
     var secondGC = result['dateLastAccumulatorReset'];