convert-from-nuget fails with ArgumentException: The option value was None Parameter name: option #3089

Description

Converting a solution with a single F# netcoreapp2.0 project fails with:

λ  .\.paket\paket.exe convert-from-nuget
Paket version 5.145.6
Performance:
 - Runtime: 555 milliseconds
Paket failed with
-> ArgumentException: The option value was None
   Parameter name: option

Repro steps

Please provide the steps required to reproduce the problem

1. Create solution with a single F# netcoreapp2.0 project.
2. Create a .paket folder in the solution folder
3. Run .paket\paket.exe convert-from-nuget

A git repository with a repro sample

Expected behavior

After executing paket.exe convert-from-nuget I expect the project to be converted to paket

Actual behavior

paket fails with an argument exception

Known workarounds

Convert to paket manually