Prevent the user from resizing the last wxDataViewCtrl column

This is useless as this column will be automatically expanded to fill
all the available space anyhow.

See #18295.

src/generic/datavgen.cpp

@@ -256,6 +256,17 @@ void wxDataViewColumn::SetSortOrder(bool ascending)
     m_owner->OnColumnChange(idx);
 }
 
+bool wxDataViewColumn::IsResizeable() const
+{
+    // The last column in generic wxDataViewCtrl is never resizeable by the
+    // user because it's always automatically expanded to consume all the
+    // available space, so prevent the user from resizing it.
+    if ( this == GetOwner()->GetColumn(GetOwner()->GetColumnCount() - 1) )
+        return false;
+
+    return wxDataViewColumnBase::IsResizeable();
+}
+
 //-----------------------------------------------------------------------------
 // wxDataViewHeaderWindow
 //-----------------------------------------------------------------------------