src/vs/workbench/contrib/notebook/common/model/notebookTextModel.ts/NotebookTextModel/_changeCellMetadataPartial
class NotebookTextModel:	private _changeCellMetadataPartial(cell: NotebookCellTextModel, metadata: NullablePartialNotebookCellMetadata, computeUndoRedo: boolean) {
		const newMetadata: NotebookCellMetadata = {
			...cell.metadata
		};
		let k: keyof NullablePartialNotebookCellMetadata;
		for (k in metadata) {
			const value = metadata[k] ?? undefined;
			newMetadata[k] = value as any;
		}

		return this._changeCellMetadata(cell, newMetadata, computeUndoRedo);
	}