patch 8.1.0152: cannot easily run individual tests on MS-Windows

Problem:    Cannot easily run individual tests on MS-Windows.
Solution:   Move the list of tests to a separate file.  Add a build rule in
            the MSVC makefile.
diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index 8cb443c..f329033 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -693,6 +693,8 @@
 ! endif
 !endif # DEBUG
 
+!include Make_all.mak
+
 INCL =	vim.h alloc.h arabic.h ascii.h ex_cmds.h farsi.h feature.h globals.h \
 	keymap.h macros.h option.h os_dos.h os_win32.h proto.h regexp.h \
 	spell.h structs.h term.h beval.h $(NBDEBUG_INCL)
@@ -1296,6 +1298,14 @@
 	$(MAKE) /NOLOGO -f Make_dos.mak clean
 	cd ..
 
+$(NEW_TESTS):
+	cd testdir
+	- if exist $@.res del $@.res
+	$(MAKE) /NOLOGO -f Make_dos.mak nolog
+	$(MAKE) /NOLOGO -f Make_dos.mak $@.res
+	$(MAKE) /NOLOGO -f Make_dos.mak report
+	cd ..
+
 ###########################################################################
 
 # Create a default rule for transforming .c files to .obj files in $(OUTDIR)