FileSystemWatcher: Prevent slot execution on deleted object

Amends 1f974bdbbf.

Change-Id: I0cdb7a096f8af62c066b6c251ac7755a4cb359a1
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/libs/utils/filesystemwatcher.cpp

@@ -142,6 +142,7 @@ public:
     {
         QObject::connect(Utils::GlobalFileChangeBlocker::instance(),
                          &Utils::GlobalFileChangeBlocker::stateChanged,
+                         q,
                          [this](bool blocked) { autoReloadPostponed(blocked); });
     }