Simplify import path in examples

To have the same path (starting with `ol/`, without `.js`) as in the documentation.
The support was added in the webpack config in #8928

examples/webpack/example-builder.js

@@ -155,7 +155,6 @@ ExampleBuilder.prototype.render = async function(dir, chunk) {
   if (!jsSource) {
     throw new Error(`No .js source for ${jsName}`);
   }
-  jsSource = jsSource.replace(/'\.\.\/src\//g, '\'');
   if (data.cloak) {
     for (const entry of data.cloak) {
       jsSource = jsSource.replace(new RegExp(entry.key, 'g'), entry.value);