Add notice of requesting source code in modulemetadata

Flag: EXEMPT license change for b/418865751
Bug: 418865751
Test: presubmits
Test: lunch husky-trunk_staging-eng && m, an extra line is added at the top of NOTICE.html file in NOTICE.html.gz
Change-Id: I87fc25c114f8d80872509a9f4b787c8f3e4ac8ff

Android.bp

diff --git a/Android.bp b/Android.bp
index c0453ac..3ba255d 100644
--- a/Android.bp
+++ b/Android.bp
@@ -30,4 +30,8 @@
     dex_preopt: {
         enabled: false,
     },
+    licenses: [
+        "Android-Apache-2.0",
+        "opensourcerequest",
+    ],
 }