appveyor.yml: download beta version for test

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67449 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
2019-04-05 14:44:13 +00:00 · 2019-04-05 14:44:13 +00:00 · 9dcc6f0810
--- a/appveyor.yml
+++ b/appveyor.yml
@ -42,7 +42,7 @@ for:
    - echo>> Makefile BUILTIN_ENCOBJS=nul
    - type win32\Makefile.sub >> Makefile
    - nmake %mflags% touch-unicode-files
-    - nmake %mflags% up incs UNICODE_FILES=.
+    - nmake %mflags% up incs
    - del Makefile
    - mkdir \usr\local\bin
    - mkdir \usr\local\include