CI/AppVeyor: fix core system upgrade

Work around pacman not being able to do fully unattended updates
in some rare cases.

See also https://github.com/Alexpux/MSYS2-packages/issues/1141

.appveyor.yml

@@ -8,7 +8,7 @@ environment:
     - MSYSTEM: MINGW32
 
 build_script:
-  - C:\msys64\usr\bin\pacman -Syuu --needed --noconfirm --noprogressbar
+  - C:\msys64\usr\bin\pacman -Syuu --needed --noconfirm --noprogressbar --ask=127
   - C:\msys64\usr\bin\bash --login -c "$(cygpath ${APPVEYOR_BUILD_FOLDER})/buildtools/appveyor.sh"
 
 artifacts:

[Tavmjong Bah]

How did this get attributed to me?

[Patrick Storz]

I messed up the rebase and squashed one commit too much (note the date of this commit is exactly the same as that of its parent which was your commit).

I hope you don't mind, good work Tav, I wouldn't have done it differently ;-)