Git: Fix memory leak

Change-Id: If9dbc29f0b58a81319b3490821edf5f7afce90ab
Reviewed-by: hjk <hjk@qt.io>

src/plugins/git/gitplugin.cpp

@@ -143,6 +143,7 @@ GitPlugin::~GitPlugin()
 {
     cleanCommitMessageFile();
     delete m_gitClient;
+    delete m_branchViewFactory;
     m_instance = nullptr;
 }