feat: Braintree Drop-in v6.16.0 (#39)

* - update metadata

* - update metadata

* - update metadata

* - com.braintreepayments.api:drop-in:6.16.0

* - com.braintreepayments.api:drop-in:6.16.0

.github/workflows/android-lib.yml

@@ -26,6 +26,7 @@ on:
         - com.paypal.android:paypal-web-payments:1.3.0
         - io.github.sceneview:sceneview:2.1.1
         - io.github.sceneview:arsceneview:2.1.1
+        - com.braintreepayments.api:drop-in:6.16.0
 jobs:
   build-then-publish:
     environment: production