Bump AppVeyor Ruby version

xzyfer · xzyfer · commit c1417f125838 · 2019-03-16T20:01:54.000+11:00
We need at least Ruby 2.3.0 for hrx
diff --git a/appveyor.yml b/appveyor.yml
@@ -2,7 +2,7 @@ os: Visual Studio 2013
 
 environment:
   CTEST_OUTPUT_ON_FAILURE: 1
-  ruby_version: 22-x64
+  ruby_version: 24-x64
   TargetPath: sassc/bin/sassc.exe
   matrix:
   - Compiler: msvc
