Add TOP to run_cuj so it runs from the correct dir

Test: locally run build/soong/cuj/run_cuj.sh
Change-Id: I89cdc91cc48349fa62840d24baf9b3818284f090
diff --git a/cuj/cuj.go b/cuj/cuj.go
index 413f423..c671f6f 100644
--- a/cuj/cuj.go
+++ b/cuj/cuj.go
@@ -138,6 +138,8 @@
 
 	cujDir := filepath.Join(outDir, "cuj_tests")
 
+	wd, _ := os.Getwd()
+	os.Setenv("TOP", wd)
 	// Use a subdirectory for the out directory for the tests to keep them isolated.
 	os.Setenv("OUT_DIR", filepath.Join(cujDir, "out"))