Add compatibility with Android Gradle Plugin 8.0 (#1039)

* Adds Android namespace

Adds a namespace attribute to the Android build.gradle, for compatibility with Android Gradle Plugin 8.0.

* Adds Android namespace

Adds a namespace attribute to the Android build.gradle, for compatibility with Android Gradle Plugin 8.0.

* Conditionalize the namespace

permission_handler_android/android/build.gradle

@@ -27,6 +27,10 @@ project.getTasks().withType(JavaCompile){
 apply plugin: 'com.android.library'
 
 android {
+    // Conditional for compatibility with AGP <4.2.
+    if (project.android.hasProperty("namespace")) {
+      namespace 'com.baseflow.permissionhandler'
+    }
     compileSdkVersion 33
 
     compileOptions {

permission_handler_android/example/android/app/build.gradle

@@ -25,6 +25,7 @@ apply plugin: 'com.android.application'
 apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
 
 android {
+    namespace 'com.baseflow.permissionhandler.example'
     compileSdkVersion 33
 
     compileOptions {