Adjust appveyor configuration

Author: Vadim Hatsura

appveyor.yml

@@ -5,11 +5,13 @@ build_script:
 - ps: ./Build.ps1 
 test: off
 artifacts:
-- path: artifacts/Serilog.Sinks.Elasticsearch*.nupkg
+  - path: artifacts/Serilog.Sinks.Elasticsearch*.nupkg
+  - path: artifacts/Serilog.Formatting.Elasticsearch*.nupkg
 only_commits:
   files:
     - serilog-sinks-elasticsearch.sln
     - src/Serilog.Sinks.Elasticsearch/
+    - src/Serilog.Formatting.Elasticsearch/
     - nuget.config
     - Build.ps1
     - assets/