Rename microdroid_launcher domain to microdroid_app

As the payload is in a shared library, microdroid_launcher domain is
used as-is when running microdroid app. This changes the domain name to
microdroid_app, because microdroid_launcher does nothing but just launch
the microdroid app.

Bug: 189706019
Test: atest MicrodroidHostTestCases
Change-Id: Id30b4a85cc1b9023a93546d33b6071863e9268ee
diff --git a/microdroid/sepolicy/system/private/domain.te b/microdroid/sepolicy/system/private/domain.te
index 4a59f73..e979f3e 100644
--- a/microdroid/sepolicy/system/private/domain.te
+++ b/microdroid/sepolicy/system/private/domain.te
@@ -216,7 +216,7 @@
     -appdomain # for oemfs
     -bootanim # for oemfs
     -recovery # for /tmp/update_binary in tmpfs
-    -microdroid_launcher -microdroid_manager # for executing shared libs on /mnt/apk in Microdroid
+    -microdroid_app -microdroid_manager # for executing shared libs on /mnt/apk in Microdroid
 } { fs_type -rootfs }:file execute;
 
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