Asset CDN: add option to exclude specific file from being served by the CDN

### Impacted plugin

Jetpack

### What

Exclude assets file from loading via Jetpack CDN

### How

In certain cases, users may want to exclude specific JavaScript (JS) or Cascading Style Sheet (CSS) files from loading via Jetpack Content Delivery Network (CDN). This feature, often available on various CDN services, would be beneficial for Jetpack users. We're also seeing some Pressable users requesting for this features which we think would be a great addition to Jetpack.

The issue names Jetpack CDN and JS/CSS assets but no files, tests, or entry points. Locate the CDN asset-serving integration, determine how users should identify files to exclude and where the option belongs, then verify that excluded assets bypass the CDN while other assets continue through it.

Written by the indexing model from the issue text.