Added version suffix to csproj

Author: merbla

src/Serilog.Sinks.Splunk/Serilog.Sinks.Splunk.csproj

@@ -13,7 +13,7 @@
     <PackageProjectUrl>https://github.com/serilog/serilog-sinks-splunk</PackageProjectUrl>
     <PackageLicenseUrl>http://www.apache.org/licenses/LICENSE-2.0</PackageLicenseUrl>
     <GenerateAssemblyVersionAttribute>false</GenerateAssemblyVersionAttribute>
-    <Version>2.2.0</Version>
+    <Version>2.2.0$(VersionSuffix)</Version>
   </PropertyGroup>
 
   <ItemGroup Condition=" '$(TargetFramework)' == 'net45' ">