Clang: Increase timeout in test

Might fix a fail on loaded test machines.

Change-Id: Ieb9e8426f760e2257ececa0b53c564d68992c3fa
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/clangcodemodel/test/clangcodecompletion_test.cpp

@@ -219,7 +219,7 @@ WaitForAsyncCompletions::WaitResult WaitForAsyncCompletions::wait(
     // There are not any, so wait for async results.
     QElapsedTimer timer; timer.start();
     while (!gotResults) {
-        if (timer.elapsed() >= 5 * 1000)
+        if (timer.elapsed() >= 30 * 1000)
             return Timeout;
         QCoreApplication::processEvents();
     }