[ci] Install ragel on appveyor mingw bots

Hopefully autotools timestamps issues will go

appveyor.yml

@@ -57,7 +57,7 @@ environment:
 
 
 install:
-  - 'if "%compiler%"=="msys2" C:\msys64\usr\bin\bash -lc "pacman --noconfirm --force -S --needed mingw-w64-$MSYS2_ARCH-{gcc,freetype,cairo,icu,gettext,gobject-introspection,gcc,gcc-libs,glib2,graphite2,pkg-config,python2}"'
+  - 'if "%compiler%"=="msys2" C:\msys64\usr\bin\bash -lc "pacman --noconfirm --force -S --needed mingw-w64-$MSYS2_ARCH-{gcc,freetype,cairo,icu,gettext,gobject-introspection,gcc,gcc-libs,glib2,graphite2,pkg-config,python2,ragel}"'
   - 'if "%compiler%"=="msvc" if not "%platform%"=="ARM" vcpkg install glib:%triplet% freetype:%triplet% cairo:%triplet%'
 
 build_script: