m/installer/test: undo leftover test comment

This was introduced by review/1365, and it was just done for testing.
Undoing this should not undo the flakiness fix.

Change-Id: I7e3096f6b09b2cbd3f3f75dfb4b3602ddfae0959
Reviewed-on: https://review.monogon.dev/c/monogon/+/1367
Reviewed-by: Leopold Schabel <leo@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/installer/test/main.go b/metropolis/installer/test/main.go
index 3963654..7954c1d 100644
--- a/metropolis/installer/test/main.go
+++ b/metropolis/installer/test/main.go
@@ -268,7 +268,7 @@
 	if err := checkEspContents(storage); err != nil {
 		t.Error(err.Error())
 	}
-	//storage.File.Close()
+	storage.File.Close()
 	// Run QEMU again. Expect TestOS to launch successfully.
 	expectedOutput = "_TESTOS_LAUNCH_SUCCESS_"
 	time.Sleep(time.Second)