Migrate THIRD-PARTY-NOTICES to markdown

Author: gehongyan

HeyBox.Net.props

@@ -48,7 +48,7 @@
   <ItemGroup>
     <None Include="../../README.md" Pack="true" PackagePath="\"/>
     <None Include="../../LICENSE" Pack="true" PackagePath="\"/>
-    <None Include="../../THIRD-PARTY-NOTICES.txt" Pack="true" PackagePath="\"/>
+    <None Include="../../THIRD-PARTY-NOTICES.md" Pack="true" PackagePath="\"/>
 <!--    <None Include="../../docs/logo/Logo_Small.png" Pack="true" PackagePath=""/>-->
   </ItemGroup>
 </Project>