Revert "Enable _FORTIFY_SOURCE=3 for Bionic"

Revert submission 3391212-_FORTIFY_SOURCE=3

Reason for revert: DroidMonitor: Potential culprit for http://b/383164857 - verifying through ABTD before revert submission. This is part of the standard investigation process, and does not mean your CL will be reverted.

Reverted changes: /q/submissionid:3391212-_FORTIFY_SOURCE%3D3

Change-Id: I41953dd148aa7269142b2f983bfd6fdab54bb311
diff --git a/tests/Android.bp b/tests/Android.bp
index 31ff582..a97f5a8 100644
--- a/tests/Android.bp
+++ b/tests/Android.bp
@@ -670,7 +670,7 @@
     ],
     cflags: [
         "-Werror",
-        "-D_FORTIFY_SOURCE=3",
+        "-D_FORTIFY_SOURCE=2",
         "-D__clang_analyzer__",
     ],
     srcs: ["clang_fortify_tests.cpp"],