docs: Remove outdated Webpack guide and example (#24478)

A supporting Webpack guide will be introduced as part of the guidance
for ejecting from the Angular CLI.

Closes #23937

PR Close #24478

aio/tools/example-zipper/exampleZipper.js

@@ -113,7 +113,6 @@ class ExampleZipper {
       '!**/package.json',
       '!**/example-config.json',
       '!**/wallaby.js',
-      '!**/package.webpack.json',
       // AoT related files
       '!**/aot/**/*.*',
       '!**/*-aot.*'