Switch from CommonJS to ESM for support for TypeDoc 0.27.x

[blutorange]

Switch from CommonJS to ESM to support TypeDoc 0.27.x. Up until now, this plugin was distributed as CommonJS. When it tries to require("typedoc"), that fails, since CommonJS can't require ESM modules and TypeDoc is now distributed as ESM.

[error] The plugin typedoc-plugin-mdn-links could not be loaded
[error] Error [ERR_REQUIRE_ESM]: require() of ES Module /home/user/foo/node_modules/typedoc/dist/index.js from /home/user/foo/node_modules/typedoc-plugin-mdn-links/dist/index.js not supported.
Instead change the require of /home/user/foo/node_modules/typedoc/dist/index.js in /home/user/foo/node_modules/typedoc-plugin-mdn-links/dist/index.js to a dynamic import() which is available in all CommonJS modules.

I tested it against Node.JS 18, which is, as far as I can tell, the lowest version that's still supported

[Gerrit0]

Shoot, I thought I'd gotten all of the CJS plugins when migrating... thanks!