🤖 config(build): Set type to module in package.json.

These changes were automatically generated by a transform whose code can be found at:
  - https://github.com/make-github-pseudonymous-again/rejuvenate/blob/a44c42967442d65fd14272682fb84a6f32feb841/src/transforms/package.json:set-type-module.js
Please contact the author of the transform if you believe there was an error.

doc/manual/usage.md

@@ -2,14 +2,14 @@
 The code needs a ES2015+ polyfill to work, for example
 [regenerator-runtime/runtime](https://babeljs.io/docs/usage/polyfill).
 ```js
-require( 'regenerator-runtime/runtime' ) ;
+await import( 'regenerator-runtime/runtime.js' ) ;
 // or
 import 'regenerator-runtime/runtime.js' ;
 ```
 
 Then
 ```js
-const persistent = require( '@functional-data-structure/persistent' ) ;
+const persistent = await import( '@functional-data-structure/persistent' ) ;
 // or
 import persistent from '@functional-data-structure/persistent' ;
 ```

package.json

@@ -20,6 +20,7 @@
     "structures"
   ],
   "sideEffects": false,
+  "type": "module",
   "source": "src/index.js",
   "main": "dist/index.cjs",
   "module": "dist/index.module.js",