vim-patch:9.0.1066: test function name is wrong

Problem:    Test function name is wrong.
Solution:   Rename to what is actually being tested. (closes vim/vim#11712)

https://github.com/vim/vim/commit/67f3094397a40bea051a8e99921a8bf6f45d6147

test/old/testdir/test_menu.vim

@@ -614,7 +614,7 @@ func Test_only_modifier()
   tunmenu a.b
 endfunc
 
-func Test_mapclear_while_listing()
+func Test_unmenu_while_listing_menus()
   CheckRunVimInTerminal
 
   let lines =<< trim END