packaging,win32: Add error check

Author: k-takata

win32/appveyor.bat

@@ -144,7 +144,7 @@ if "%normalbuild%"=="no" (
 :: Install necessary packages
 bash -lc "for i in {1..3}; do pacman --noconfirm --noprogressbar -S --needed mingw-w64-%MSYS2_ARCH%-{jansson,libxml2,libyaml,pcre2} autoconf automake && break || sleep 15; done"
 
-bash -lc "./autogen.sh"
+bash -lc "./autogen.sh" || exit 1
 :: Use static link.
 bash -lc "./configure --disable-external-sort --enable-static && make -j2"