Updated interactive project to support net7.0 and n6.0

We'll use 6.0 since that is the environment that is supported by dotnet interactive for now

Author: Paul Joiner

Dockerfile

@@ -42,11 +42,11 @@ RUN apt-get update \
 # Install .NET Core SDK
 
 # When updating the SDK version, the sha512 value a few lines down must also be updated.
-ENV DOTNET_SDK_VERSION 7.0.100
+ENV DOTNET_SDK_VERSION 6.0.100
 
-RUN dotnet_sdk_version=7.0.100 \
+RUN dotnet_sdk_version=6.0.100 \
     && curl -SL --output dotnet.tar.gz https://dotnetcli.azureedge.net/dotnet/Sdk/$dotnet_sdk_version/dotnet-sdk-$dotnet_sdk_version-linux-x64.tar.gz \
-    && dotnet_sha512='0a2e74486357a3ee16abb551ecd828836f90d8744d6e2b6b83556395c872090d9e5166f92a8d050331333d07d112c4b27e87100ba1af86cac8a37f1aee953078' \
+  && dotnet_sha512='cb0d174a79d6294c302261b645dba6a479da8f7cf6c1fe15ae6998bc09c5e0baec810822f9e0104e84b0efd51fdc0333306cb2a0a6fcdbaf515a8ad8cf1af25b' \
     && echo "$dotnet_sha512 dotnet.tar.gz" | sha512sum -c - \
     && mkdir -p /usr/share/dotnet \
     && tar -ozxf dotnet.tar.gz -C /usr/share/dotnet \

src/DwC-A_dotnet.Interactive/DwC-A_dotnet.Interactive.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFrameworks>net6.0;net7.0</TargetFrameworks>
     <RootNamespace>DwC_A.Interactive</RootNamespace>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <Copyright>Copyright © Paul Joiner 2021</Copyright>
@@ -36,7 +36,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <None Include="$(OutputPath)/DwC-A_dotnet.Interactive.dll" Pack="true" PackagePath="interactive-extensions/dotnet" />
+    <None Include="$(OutputPath)/net6.0/DwC-A_dotnet.Interactive.dll" Pack="true" PackagePath="interactive-extensions/dotnet" />
     <None Include="..\..\LICENSE"  Pack="true" PackagePath="\" />
     <None Include="..\..\README.md" Pack="true" PackagePath="\" />
   </ItemGroup>