www/caddy: Update to 2.5.0

Changes:

Highlights

• Reverse proxy: ✨ Dynamic upstreams, which is the ability to get the list of upstreams at every request (more specifically, every iteration in the proxy loop of every request) rather than just once at config-load time. Dynamic upstream modules can be plugged in to provide Caddy with the latest list of backends in real-time. Two standard modules have been implemented which can get upstreams from SRV and A/AAAA record lookups.
  
  *⚠️This deprecates the lookup_srv JSON field for upstreams (and srv+ scheme prefix in the Caddyfile), which will be removed in the future.

• Automatic HTTPS: Caddy will automatically try to get relevant certificates from the local Tailscale instance (if running with permission to access the Tailscale socket). This makes services running on a Tailscale network automatically available over trusted HTTPS with Caddy.

• Tracing: New OpenTelemetry integration with the tracing handler module and associated tracing directive.

• Reverse proxy: When using the response handlers, a new handler copy_response is available to copy the proxy's response back to the client, and copy_response_headers may be used to selectively copy header values from the proxy's response.

• API: Added new endpoints /pki/ca/<id> and /pki/ca/<id>/certificates for getting information about Caddy's managed CAs, including the chain of root and intermediate certificates.

Full changes: https://github.com/caddyserver/caddy/releases/tag/v2.5.0