Fix warning spam when building

[Therzok]

/Users/builder/azdo/_work/1/s/main/external/fsharp-editor/vsintegration/src/FSharp.Editor/unknown(1,1): warning FS3384: The .NET SDK for this script could not be determined. If the script is in a directory using a 'global.json' then ensure the relevant .NET SDK is installed. The output from '/usr/local/share/dotnet/dotnet --version' in the directory '/Users/builder/azdo/_work/1/s/main/external/fsharp-editor/vsintegration/src/FSharp.Editor' was: 'Could not execute because the application was not found or a compatible .NET SDK is not installed.�Possible reasons for this include:�  * You intended to execute a .NET program:�      The application '--version' does not exist.�  * You intended to execute a .NET SDK command:�      A compatible installed .NET SDK for global.json version [5.0.100] from [/Users/builder/azdo/_work/1/s/main/external/fsharp-editor/global.json] was not found.�      Install the [5.0.100] .NET SDK or update [/Users/builder/azdo/_work/1/s/main/external/fsharp-editor/global.json] with an installed .NET SDK:' and the exit code was '145'. [/Users/builder/azdo/_work/1/s/main/external/fsharp-editor/vsintegration/src/FSharp.Editor/FSharp.Editor.fsproj]

Bump the SDK version to avoid this.