export app plugin for expo (#316)

Author: jasonpraful

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@intercom/intercom-react-native",
-  "version": "9.0.0-beta.2",
+  "version": "9.0.0-beta.3",
   "description": "React Native wrapper to bridge our iOS and Android SDK",
   "source": "./src/index.tsx",
   "main": "./lib/commonjs/index.js",
@@ -25,6 +25,7 @@
         "default": "./lib/commonjs/index.js"
       }
     },
+    "./app.plugin.js": "./app.plugin.js",
     "./package.json": "./package.json"
   },
   "files": [