Fix url encoding - only workaround so far

[johbo]

Got a problem with scoped packages, they have a name like @type/clone, got the following in the output:

http 404 https://registry.npmjs.org/@types/clone/
Error during fetch: Error getting registry info for @types/clone: Error: Not found : @types

When I tried the URL in the browser, I found that changing it to @types%2fclone/ works fine.

At the moment the attached change is just a workaround which made it work for me. I am quite sure that this is not the best approach though. Hope I can get some hint how to improve it.