Ensure current cell remains valid when wxGrid table changes

Replacing the table used by the grid could make the current cell
coordinates invalid, resulting in asserts when trying to use it later.
Fix this by calling the same function which was already called when
changing the existing table.

See #23752.

Closes #23751.

Co-authored-by: Vadim Zeitlin <vadim@wxwidgets.org>

src/generic/grid.cpp

@@ -2912,6 +2912,8 @@ wxGrid::SetTable(wxGridTableBase *table,
 
     InvalidateBestSize();
 
+    UpdateCurrentCellOnRedim();
+
     return m_created;
 }