component/caddy: Upgrade to v1.0.0-beta1

This also means that caddy source is fetched directly from upstream, as all required fixes has been incorporated into the upstream.

Since https://github.com/mholt/caddy/releases/tag/v0.11.4 TLS-SNI challenge is replaced by ACME TLS-ALPN challenge, so switch has changed.

Drop direct usage of gowork for now, in order to have caddy built using go module, support for gowork with go modules might come later.