Fixup saving non-data changes on database lock

* Fix #5107 
* Change setting for non-data changes to Auto save on database lock (or not) instead of marking modified.
* When enabled, database will be auto-saved if there are only non-data changes, but will not prompt the user if saving has failed.
* When disabled, database will not auto-save if there are only non-data changes (same behavior as 2.5 and below) and will not mark the database dirty.

src/gui/DatabaseWidget.h

@@ -260,6 +260,7 @@ private:
     void openDatabaseFromEntry(const Entry* entry, bool inBackground = true);
     bool confirmDeleteEntries(QList<Entry*> entries, bool permanent);
     void performIconDownloads(const QList<Entry*>& entries, bool force = false);
+    bool performSave(QString& errorMessage, const QString& fileName = {});
     Entry* currentSelectedEntry();
 
     QSharedPointer<Database> m_db;