replace Manifest package with Gradle namespace (#3007)

app/build.gradle

@@ -22,6 +22,7 @@ android {
     compileSdkVersion 33
     defaultConfig {
         applicationId APP_ID
+        namespace "com.keylesspalace.tusky"
         minSdkVersion 23
         targetSdkVersion 33
         versionCode 97

app/src/main/AndroidManifest.xml

@@ -1,7 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:tools="http://schemas.android.com/tools"
-    package="com.keylesspalace.tusky">
+    xmlns:tools="http://schemas.android.com/tools" >
 
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />