Explicitly set proguard_compatibility for updatable-media

This currently defaults to proguard_compatibility, which is made explicit by this change.

This ensures that this target will not be affected by changing the default value of proguard_compatibility to false.

Bug: 215530220
Test: existing
Change-Id: I40450d6fec6bee73eb21e89d965aa2703922f7fd

apex/framework/Android.bp

diff --git a/apex/framework/Android.bp b/apex/framework/Android.bp
index 05cd56c..7ea9cba 100644
--- a/apex/framework/Android.bp
+++ b/apex/framework/Android.bp
@@ -34,6 +34,7 @@
     optimize: {
         enabled: true,
         shrink: true,
+        proguard_compatibility: true,
         proguard_flags_files: ["updatable-media-proguard.flags"],
     },