Utils: make column of convertPosition 0-based to merge it into Position

Change-Id: I239b3cb33b8ad59ac4097c919155ab5ca7d57b8e
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Jarek Kobus <jaroslaw.kobus@qt.io>

src/plugins/texteditor/texteditor.cpp

@@ -3331,7 +3331,7 @@ void TextEditorWidget::restoreState(const QByteArray &state)
 
     d->m_lastCursorChangeWasInteresting = false; // avoid adding last position to history
     // line is 1-based, column is 0-based
-    gotoLine(lineVal, columnVal - 1);
+    gotoLine(lineVal, columnVal);
     verticalScrollBar()->setValue(vval);
     horizontalScrollBar()->setValue(hval);