function getLineItems(sOriginalLineItems, fnModifyData, iSkip, iTop) {
		const oLineItems = JSON.parse(sOriginalLineItems);
		if (fnModifyData) {
			fnModifyData(oLineItems.d.results);
		}
		if (iSkip || iTop) {
			iSkip = iSkip || 0;
			iTop = iSkip + (iTop || 4);
			oLineItems.d.results = oLineItems.d.results.slice(iSkip, iTop);
		}
		return JSON.stringify(oLineItems);
	}
Returns a copy of the given line item data after applying the given callback to modify the data and the
given skip and top.

@param {string} sOriginalLineItems
  The original stringified data for the line items
@param {function} [fnModifyData]
  Function which modifies the data to fit the current testcase. Gets passed an array with
  the line items
@param {number} [iSkip=0]
  The number of skipped line items
@param {number} [iTop=4]
  The maximum number of returned line items
@return {string}
  The strigified OData response for the SalesOrderLineItemSet considering the given skip and top