Fails to start/activate without internet connection

[runeksvendsen]

Steps to reproduce

1. Disable internet access (I disable wifi on my laptop)
2. Run command "Developer: Restart Extension Host"

Result

Error popup saying Couldn't get the latest haskell-language-server releases from GitHub: getaddrinfo ENOTFOUND api.github.com and the extension is not started/activated.

Expected

A warning popup is shown, notifying the user that the server could not be updated, but the current version of the extension is started/activated.

[jneira]

Agree, the behaviour should be changed. However once we add an option to disable auto download/update it could be used as a workaround: #281