Doc: Replace type by class in QWERPHPRequest

qdoc has magic to remove the 'This XXX class' in the class overview,
but not type. See e.g.
http://doc-snapshots.qt.io/qt5-5.11/qtwebengine-modules.html



Change-Id: Idd38a860ae08c7199c322d16c3ccc737972131a0
Reviewed-by: Viktor Engelmann <viktor.engelmann@qt.io>

src/core/api/qwebengineregisterprotocolhandlerpermissionrequest.cpp

@@ -47,7 +47,7 @@ QT_BEGIN_NAMESPACE
     \class QWebEngineRegisterProtocolHandlerPermissionRequest
     \inmodule QtWebEngineCore
     \since 5.11
-    \brief The QWebEngineRegisterProtocolHandlerPermissionRequest type enables
+    \brief The QWebEngineRegisterProtocolHandlerPermissionRequest class enables
     accepting or rejecting requests from the \l registerProtocolHandler API.
 
     \sa QWebEnginePage::registerProtocolHandlerPermissionRequested