command/login: Fix browser launcher for WSL users
command/login: Fix browser launcher for WSL users

With the current implementation of terraform login, Windows Subsystem
for Linux fails to open a browser due to lack of support for xdg-open.
This commit reuses a fix from pkg/browser#8 which detects a WSL
environment and uses cmd.exe to open the URL instead.

ewbankkit/terraform,VladRassokhin/terraform,heimweh/terraform,VladRassokhin/terraform,hashicorp/terraform,tommynsong/terraform,VladRassokhin/terraform,apparentlymart/terraform,pryorda/terraform,pdecat/terraform,tommynsong/terraform,pryorda/terraform,ewbankkit/terraform,apparentlymart/terraform,ewbankkit/terraform,rnaveiras/terraform,ewbankkit/terraform,hashicorp/terraform,pdecat/terraform,heimweh/terraform,hashicorp/terraform,pryorda/terraform,heimweh/terraform,heimweh/terraform,tommynsong/terraform,heimweh/terraform,apparentlymart/terraform,apparentlymart/terraform,pdecat/terraform,pdecat/terraform,VladRassokhin/terraform,rnaveiras/terraform,apparentlymart/terraform,rnaveiras/terraform