CppTools: Fix hanging test on OSX

Temporary directory is created in a folder having a symbolic link,
verification was done with the unresolved path and failed.

Change-Id: I40c943a307fe136a0f3f6fdbea5145296a63a19e
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@theqtcompany.com>

src/plugins/cpptools/cpptoolstestcase.cpp

@@ -268,7 +268,8 @@ void ProjectOpenerAndCloser::onGcFinished()
 }
 
 TemporaryDir::TemporaryDir()
-    : m_temporaryDir(QDir::tempPath() + QLatin1String("/qtcreator-tests-XXXXXX"))
+    : m_temporaryDir(QFileInfo(QDir::tempPath()).canonicalFilePath()
+                        + QLatin1String("/qtcreator-tests-XXXXXX"))
     , m_isValid(m_temporaryDir.isValid())
 {
 }