Eleventy Bundle Plugin v2.0 (bundled with Eleventy 3.0)

• Preparation to bundle this plugin with Eleventy 3.0, no longer requiring separate installation.
• Throws an error when used with incompatible Eleventy versions.
• Adds new addBundle method to eleventyConfig for better userspace JavaScript API
• Add option to set file extension separate from bundle name #22
• Handle multiple addPlugin calls.
• Skip out of order transform if no bundles in play or if page being processed did not fetch bundles.
• Changes tests to use ESM and Eleventy 3.0
• Breaking: Node 18+

Full Changelog: v1.0.5...v2.0.0