Install libxml2 and libxslt

Author: clanmills

mingw.yml

@@ -25,7 +25,7 @@ install:
     - cd %APPVEYOR_BUILD_FOLDER%
     - set "PATH=c:\cygwin64\usr\local\bin;c:\cygwin64\bin;c:\cygwin64\usr\bin;c:\cygwin64\usr\sbin;"
     - C:\cygwin64\bin\bash -c "wget https://raw.githubusercontent.com/transcode-open/apt-cyg/master/apt-cyg ; chmod +x apt-cyg; mv apt-cyg /usr/local/bin"
-    - C:\cygwin64\bin\bash -c "apt-cyg install cmake zlib-devel libexpat-devel python38 python38-pip"
+    - C:\cygwin64\bin\bash -c "apt-cyg install cmake zlib-devel libexpat-devel libxml2-devel libxslt-devel python38 python38-pip"
     - C:\cygwin64\bin\bash -c "pip3 install lxml"
 
 build_script: