Don't use zip files when creating filesystems

The end result is a directory that's passed to build_image, so zipping
and then unzipping image contents will unnecessarily slow things down.

Bug: 329146343
Test: m microdroid --no-skip-soong-tests
Change-Id: I98223c60e8144d6c707832fcc03ba8fe94467e7b
diff --git a/filesystem/filesystem_test.go b/filesystem/filesystem_test.go
index c448105..f09ed08 100644
--- a/filesystem/filesystem_test.go
+++ b/filesystem/filesystem_test.go
@@ -270,7 +270,7 @@
 		}
 	`)
 
-	inputs := result.ModuleForTests("myfilesystem", "android_common").Output("deps.zip").Implicits
+	inputs := result.ModuleForTests("myfilesystem", "android_common").Output("myfilesystem.img").Implicits
 	android.AssertStringListContains(t, "filesystem should have libbar even for unbundled build",
 		inputs.Strings(),
 		"out/soong/.intermediates/libbar/android_arm64_armv8-a_shared/libbar.so")
@@ -314,7 +314,7 @@
 	`)
 
 	filesystem := result.ModuleForTests("myfilesystem", "android_common_cov")
-	inputs := filesystem.Output("deps.zip").Implicits
+	inputs := filesystem.Output("myfilesystem.img").Implicits
 	android.AssertStringListContains(t, "filesystem should have libfoo(cov)",
 		inputs.Strings(),
 		"out/soong/.intermediates/libfoo/android_arm64_armv8-a_shared_cov/libfoo.so")