Export Soong module type to LOCAL_SOONG_MODULE_TYPE to Make for SBOM generation.

Bug: 266726655
Test: CI

Change-Id: If5b1a77930a591b6061ca2749c9c5ad29b4491fb
diff --git a/etc/prebuilt_etc_test.go b/etc/prebuilt_etc_test.go
index a6477dd..0d44c31 100644
--- a/etc/prebuilt_etc_test.go
+++ b/etc/prebuilt_etc_test.go
@@ -140,6 +140,7 @@
 		"LOCAL_REQUIRED_MODULES":        {"modA", "moduleB"},
 		"LOCAL_HOST_REQUIRED_MODULES":   {"hostModA", "hostModB"},
 		"LOCAL_TARGET_REQUIRED_MODULES": {"targetModA"},
+		"LOCAL_SOONG_MODULE_TYPE":       {"prebuilt_etc"},
 	}
 
 	mod := result.Module("foo", "android_arm64_armv8-a").(*PrebuiltEtc)