Drop no longer suported .NETCore 3.1

Author: kzu

src/dotnet-tor/dotnet-tor.csproj

@@ -3,7 +3,7 @@
   <PropertyGroup>
     <AssemblyName>dotnet-tor</AssemblyName>
     <OutputType>Exe</OutputType>
-    <TargetFrameworks>netcoreapp3.1;net6.0</TargetFrameworks>
+    <TargetFramework>net6.0</TargetFramework>
     <LangVersion>latest</LangVersion>
     <PackAsTool>true</PackAsTool>
     <PackageId>dotnet-tor</PackageId>

src/dotnet-tor/readme.md

@@ -1,5 +1,5 @@
-<!-- include ../../readme.md#content -->
-<!-- include https://github.com/devlooped/sponsors/raw/main/footer.md -->
-
-<!-- Exclude from auto-expansion in CI -->
+<!-- include ../../readme.md#content -->
+<!-- include https://github.com/devlooped/sponsors/raw/main/footer.md -->
+
+<!-- Exclude from auto-expansion in CI -->
 <!-- exclude -->