Update webpack and testing frameworks

src/export/formatter.spec.ts

@@ -1,7 +1,7 @@
 import { assert, expect } from "chai";
 import * as sinon from "sinon";
 
-import { Formatter } from "export/formatter";
+import { Formatter } from "@export/formatter";
 import { Paragraph, TextRun } from "file";
 import { CoreProperties } from "file/core-properties";
 import { Attributes } from "file/xml-components";