[Dashboard] Libman restoring delay for @fortawesome/fontawesome-free@5.6.3

Hi,

I use libman to manage dashboard assets and it seem to fail sometimes for `@fortawesome/fontawesome-free`, the provider is `unpkg`. (The `cdnjs` provider, does not have fontawesome 5)

I will make a PR if I found a solution but i don't understand the reason, maybe unpkg has some hosting problems, I don't know