fix: resolve unneeded error being thrown (#1503)

resolves: https://blocknote-js.sentry.io/issues/32147104

The drag over handler is listening to the root element, so you are not guaranteed to be hovering over a table: https://github.com/TypeCellOS/BlockNote/blob/aed9fb5044a0da73276c322b685dd838193247d0/packages/core/src/extensions/TableHandles/TableHandlesPlugin.ts#L186-L189 in which case, the previous state should still be maintained for the drop to actually switch the rows

Author: nperez0111

packages/core/src/extensions/TableHandles/TableHandlesPlugin.ts

@@ -394,9 +394,7 @@ export class TableHandlesView<
         (element) => element.tagName === "TD" || element.tagName === "TH"
       );
     if (tableCellElements.length === 0) {
-      throw new Error(
-        "Could not find table cell element that the mouse cursor is hovering over."
-      );
+      return;
     }
     const tableCellElement = tableCellElements[0];