[@types/webpack] Adding missing webpack property "version" (#34440)

* Adding missing version property

Closes #34434

* Changing void for undefined

* Removing trailing space

types/webpack/index.d.ts

@@ -16,6 +16,7 @@
 //                 Ryan Waskiewicz <https://github.com/rwaskiewicz>
 //                 Kyle Uehlein <https://github.com/kuehlein>
 //                 Grgur Grisogono <https://github.com/grgur>
+//                 Rubens Pinheiro Gonçalves Cavalcante <https://github.com/rubenspgcavalcante>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.3
 
@@ -43,6 +44,9 @@ declare function webpack(
 declare function webpack(options: webpack.Configuration[]): webpack.MultiCompiler;
 
 declare namespace webpack {
+    /** Webpack package version. */
+    const version: string | undefined;
+
     interface Configuration {
         /** Enable production optimizations or development hints. */
         mode?: "development" | "production" | "none";