I tried several times with Trellis/Bedrock from scratch and the error persist. Any petition to raw.githubusercontent.com from here is refused and my network seems to be OK (I have Internet with no problems. I have no proxies).
$ curl https://raw.githubusercontent.com/wp-cli/wp-cli/v2.3.0/utils/wp-completion.bash
curl: (7) Failed to connect to raw.githubusercontent.com port 443: Connection refused
Ok, this is the situation: The Spanish government and the judicial system, as a result of the riots in Catalonia, ordered subverting the DNS to raw.githubusercontent.com, which from the Spanish ISPs resolves to 127.0.0.1
I have changed the DNS for those of cloudflare and everything works again. But everything is that my ISP, in a telephone consultation, told me that it was not his responsibility because the ping itself was returned.
I have lost days of work for this government fudge