fix exception when dotnet cli is not installed.
fix exception when dotnet cli is not installed.

MiloszKrajewski/FAKE,beeker/FAKE,Kazark/FAKE,rflechner/FAKE,beeker/FAKE,beeker/FAKE,rflechner/FAKE,Kazark/FAKE,MiloszKrajewski/FAKE,Kazark/FAKE,rflechner/FAKE,rflechner/FAKE,MiloszKrajewski/FAKE,MiloszKrajewski/FAKE,beeker/FAKE,Kazark/FAKE