Update version to 11.1.1.

Author: grokys

build/SharedVersion.props

@@ -2,7 +2,7 @@
   xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup>
     <Product>Avalonia</Product>
-    <Version>11.1.999</Version>
+    <Version>11.1.1</Version>
     <Authors>Avalonia Team</Authors>
     <Copyright>Copyright 2013-$([System.DateTime]::Now.ToString(`yyyy`)) &#169; The AvaloniaUI Project</Copyright>
     <PackageProjectUrl>https://avaloniaui.net</PackageProjectUrl>