Update appveyor.yml

Author: DirtyF

appveyor.yml

@@ -10,12 +10,11 @@ environment:
   JEKYLL_VERSION: "~> 3.8"
   matrix:
     - RUBY_FOLDER_VER: "26"
-      JEKYLL_VERSION : "~> 3.7.4"
+      JEKYLL_VERSION : "~> 3.8.5"
     - RUBY_FOLDER_VER: "26"
       JEKYLL_VERSION : ">= 4.0.0"
     - RUBY_FOLDER_VER: "26"
     - RUBY_FOLDER_VER: "24"
-    - RUBY_FOLDER_VER: "23"
 
 install:
   - SET PATH=C:\Ruby%RUBY_FOLDER_VER%-x64\bin;%PATH%