cmd/tests: Test using %%0-%%9 as loop variables.

Based on a test case from Dimitry Sokolov.

Signed-off-by: Eric Pouech <epouech@codeweavers.com>

programs/cmd/tests/test_builtins.cmd

@@ -744,6 +744,8 @@ echo '%~xs1'
 goto :eof
 :endEchoFuns
 
+echo --- in digit variables
+for %%0 in (a b) do echo %%0 %%1 %%2
 echo ------------ Testing parameter zero ------------
 call :func parm1 parm2
 goto :endParm0

programs/cmd/tests/test_builtins.cmd.exp

@@ -600,6 +600,9 @@ N
 @drive@
 ''
 '.eh'@or_broken@''
+--- in digit variables
+@todo_wine@a %1 %2
+@todo_wine@b %1 %2
 ------------ Testing parameter zero ------------
 :func parm1
 [:func] [@drive@] [@path@] [test] [.cmd] [@drive@@shortpath@test.cmd]