Also integrate Android AAR libraries

This works in the same way as JARs are currently provided by dependencies,
and becomes necessary when needing e.g. the Android support/compat libs
for implementing the Java side of a library.

While this is not relevant (yet?) for Qt itself, we hit this with KDE's
notification framework.

Change-Id: Ia87d1a048a493f7bc311abf5761f33d1943cfbe9
Reviewed-by: BogDan Vatra <bogdan@kdab.com>

src/android/templates/build.gradle

@@ -17,7 +17,7 @@ repositories {
 apply plugin: 'com.android.application'
 
 dependencies {
-    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    implementation fileTree(dir: 'libs', include: ['*.jar', '*.aar'])
 }
 
 android {