fix null safety

android/app/src/dev/AndroidManifest.xml

@@ -1,5 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="com.mokkon.fcs_dev.fcs">
+    package="com.mokkon.fcs.fcs">
     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
 
     <!-- io.flutter.app.FlutterApplication is an android.app.Application that
@@ -15,7 +15,6 @@
             android:name=".MainActivity"
             android:launchMode="singleTop"
             android:theme="@style/LaunchTheme"
-            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
             android:hardwareAccelerated="true"
             android:windowSoftInputMode="adjustResize">
             <!-- This keeps the window background of the activity showing