patch 8.1.2259: running tests may leave XfakeHOME behind

Problem:    Running tests may leave XfakeHOME behind.
Solution:   Source summarize.vim without using setup.vim. (closes #5177)
            Also fix that on MS-Windows the test log isn't echoed.
diff --git a/src/testdir/Make_dos.mak b/src/testdir/Make_dos.mak
index 7aec010..66839d6 100644
--- a/src/testdir/Make_dos.mak
+++ b/src/testdir/Make_dos.mak
@@ -75,7 +75,7 @@
 	$(VIMPROG) -u NONE $(NO_INITS) -S summarize.vim messages
 	@echo.
 	@echo Test results:
-	@type test_result.log
+	@cmd /c type test_result.log
 	@if exist test.log ( echo TEST FAILURE & exit /b 1 ) \
 		else ( echo ALL DONE )