Add VersionPrefix

Author: worldbeater

Source/OxyPlot.Avalonia/OxyPlot.Avalonia.csproj

@@ -11,6 +11,7 @@
     <PackageTags>plotting plot charting chart</PackageTags>
     <RepositoryType>git</RepositoryType>
     <RepositoryUrl>https://github.com/oxyplot/oxyplot.git</RepositoryUrl>
+    <VersionPrefix>2.1.0</VersionPrefix>
   </PropertyGroup>
   <ItemGroup>
     <EmbeddedResource Include="**\*.xaml;Assets\*" Exclude="bin\**;obj\**;**\*.xproj;packages\**;@(EmbeddedResource)" />