Sqlite: Add excute to the database

To execute some simple pragmas etc..

Change-Id: Iaa74406a182897dd55ee3ee8dc4d4b94bb8a8e11
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/libs/sqlite/sqlitedatabase.h

@@ -64,6 +64,8 @@ public:
     int changesCount();
     int totalChangesCount();
 
+    void execute(Utils::SmallStringView sqlStatement);
+
 private:
     void initializeTables();
     SqliteDatabaseBackend &backend();