chore: fix mobile install script

packages/mobile/README.md

@@ -31,7 +31,7 @@ This is a React Native implementation of Standard Notes. React Native allows us
 4. Install project dependencies via:
 
 ```shell
-yarn install
+yarn install && yarn install:pods
 ```
 
 We have two flavors of the app:

packages/mobile/package.json

@@ -16,7 +16,8 @@
     "lint:prettier": "prettier ./src --write",
     "tsc": "tsc --noEmit",
     "start": "react-native start",
-    "postinstall": "patch-package && yarn pod-install ios",
+    "install:pods": "yarn pod-install ios",
+    "postinstall": "patch-package",
     "android:bundle": "react-native bundle --platform android --dev false --entry-file index.js --bundle-output android/app/src/main/assets/index.android.bundle --assets-dest android/app/build/intermediates/res/merged/release/",
     "upgrade:snjs": "ncu -u '@standardnotes/*' && yarn"
   },