Revert "Add seapp_contexts to allowlist of makefile goal"

Revert submission 1795972-Convert security/Android.mk to Android.bp

Reason for revert: http://b/206976319 Broken build 7928060 on aosp-master on sdk_arm64-sdk
Reverted Changes:
I0e0e7f677:Split property and file contexts modules
I5596d6f00:Add seapp_contexts to allowlist of makefile goal
If685e5ccc:Convert security/Android.mk to Android.bp

Change-Id: I8cf8c0bc2f88172bb3bfa850bbd7ce6daa170c3d

android/neverallow_test.go

@@ -293,7 +293,7 @@ var neverallowTests = []struct {
 			`),
 		},
 		expectedErrors: []string{
-			"Only boot images and seapp contexts may be imported as a makefile goal.",
+			"Only boot images may be imported as a makefile goal.",
 		},
 	},
 }