tests: recovery_unit_test requires root.

Bug: 141272654
Test: TreeHugger (recovery_unit_test no longer fails)
Change-Id: I47cbee274e659e3d90be5a77b215466d2973c7d6
diff --git a/tests/Android.bp b/tests/Android.bp
index 232697d..3335c0b 100644
--- a/tests/Android.bp
+++ b/tests/Android.bp
@@ -99,6 +99,7 @@
 cc_test {
     name: "recovery_unit_test",
     isolated: true,
+    require_root: true,
 
     defaults: [
         "recovery_test_defaults",