Disable SHAMapStore test:

The test depends on an asynchronous operation completing
in a certain time, failing periodically due to timing.

src/ripple/app/tests/SHAMapStore_test.cpp

@@ -648,7 +648,8 @@ public:
     }
 };
 
-BEAST_DEFINE_TESTSUITE(SHAMapStore,app,ripple);
+// VFALCO This test fails because of thread asynchronous issues
+BEAST_DEFINE_TESTSUITE_MANUAL(SHAMapStore,app,ripple);
 
 }
 }