Set min_sdk_version to be part of mainline modules

Modules contributing mainline modules (APK/APEX) should set
min_sdk_version as well as apex_available.

For now setting min_sdk_version doesn't change build outputs.
But build-time checks will be added soon.

Bug: 152655956
Test: m
Merged-In: I6e251b193a1ee4dc868b17a67b0d730ecd678d8b
Change-Id: I6e251b193a1ee4dc868b17a67b0d730ecd678d8b
(cherry picked from commit 3671db5c134991149ced59813e4a47029942e273)
diff --git a/Android.bp b/Android.bp
index b809a9f..2ef1e5d 100644
--- a/Android.bp
+++ b/Android.bp
@@ -45,6 +45,7 @@
         "//apex_available:anyapex",
     ],
     native_bridge_supported: true,
+    min_sdk_version: "29",
 }
 
 cc_library_static {