Remove old version category session data on startup

Saved category pairs seperated by '|' is from old version

src/settingsmanager.cpp

@@ -186,5 +186,11 @@ void SettingsManager::initSettings()
     m_langList = m_settings.value("language", defaultLangVariant).toList();
 
     m_categoryList = m_settings.value("category", {}).toStringList();
+
+    /* Porting with older version: category pairs seperated with "|" 
+       are removed to avoid user confusion.
+    */
+    setCategory(m_categoryList.filter(QRegularExpression(R"(^[^|]*$)")));
+
     m_contentTypeList = m_settings.value("contentType", {}).toList();
 }