Export package.json (node-fetch#908)

* Export package.json

* Correct exports structure to support multiple modules

Author: wheresrhys

package.json

@@ -7,8 +7,11 @@
 	"sideEffects": false,
 	"type": "module",
 	"exports": {
-		"import": "./src/index.js",
-		"require": "./dist/index.cjs"
+    ".": {
+      "import": "./src/index.js",
+      "require": "./dist/index.cjs"
+    },
+    "./package.json": "./package.json"
 	},
 	"files": [
 		"src",