dns/blocky: update to 0.19

ChangeLog: https://github.com/0xERR0R/blocky/releases/tag/v0.19

Features:

• Add rewrite support to custom DNS
• CustomDNS: parameter "filterUnmappedTypes" to allow/disable forwarding to
• the upstream resolver
• filtering of queries
• Support of DoH/DoT as bootstrap DNS
• Memory optimization internal blacklist/whitelist cache
• Cache refresh memory consumption optimization
• Enable "ForceAttemptHTTP2" for DoH upstreamClient
• Improve DoT server TLS cipher suites
• Hide DoH client http header "User-Agent"
• Add HTTP Secure Headers on HTTPS server response
• Make DoH/DoT server mininum TLS version configurable
• Adds user customizable DoH upstream user agent
• Support for multiple configuration files
• Self-signed certificate generation

Misc

• Updated dependencies and documentation
• Environment variable for configurable config file location

Reported by: portscout