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[Regression] Stream API fails to write XLSX files

See original GitHub issue

Since version 0.2.10, exceljs fails to write xlsx files using the stream API with the following error:

Unhandled rejection Error: append: input source must be valid Stream or Buffer instance
    at Archiver.append (/home/bugreport/backend/node_modules/archiver/lib/core.js:333:24)
    at /home/bugreport/backend/node_modules/exceljs/lib/stream/xlsx/workbook-writer.js:251:18
    at Promise._execute (/home/bugreport/backend/node_modules/bluebird/js/release/debuggability.js:272:9)
    at Promise._resolveFromExecutor (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:475:18)
    at new Promise (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:77:14)
    at Object.WorkbookWriter.addSharedStrings (/home/bugreport/backend/node_modules/exceljs/lib/stream/xlsx/workbook-writer.js:250:14)
    at /home/bugreport/backend/node_modules/exceljs/lib/stream/xlsx/workbook-writer.js:131:16
    at tryCatcher (/home/bugreport/backend/node_modules/bluebird/js/release/util.js:16:23)
    at Promise._settlePromiseFromHandler (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:504:31)
    at Promise._settlePromise (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:561:18)
    at Promise._settlePromise0 (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:606:10)
    at Promise._settlePromises (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:685:18)
    at Promise._fulfill (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:630:18)
    at Promise._resolveCallback (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:447:14)
    at Promise._settlePromiseFromHandler (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:516:17)
    at Promise._settlePromise (/home/bugreport/backend/node_modules/bluebird/js/release/promise.js:561:18)

This is the code to reproduce the problem:

const fs = require('fs');
const Excel = require('exceljs');

let outStream = fs.createWriteStream('/tmp/aaa', {flags: 'w'})

let options = {
    stream: outStream,
    useStyles: true,
    useSharedStrings: true
};

let workbook = new Excel.stream.xlsx.WorkbookWriter(options);
let worksheet = workbook.addWorksheet('test');
let newrow = worksheet.addRow(['hello']);
newrow.commit();
worksheet.commit();
workbook.commit();

If you do not add any row, it works fine. Also, worked fine on 0.2.9 and previous versions.