security/snowflake-tor: update 2.1.0 to 2.3.0

  * while here,
    - add 'broker' support;
    - add 'tor' as RUN_DEPENDS, as broker uses its geoip databases;
    - add rc script to start a local broker without TLS support.

  Changes in version v2.3.0
  - Issue 40146: Avoid performing two NAT probe tests at startup
  - Issue 40134: Log messages from client NAT check failures are confuse
  - Issue 34075: Implement metrics to measure snowflake churn
  - Issue 28651: Prepare all pieces of the pipeline for a second bridge
  - Issue 40129: Distributed Snowflake Server Support

  Changes in version v2.2.0
  - Issue 40099: Initialize SnowflakeListener.closed
  - Add connection failure events for proxy timeouts
  - Issue 40103: Fix proxy logging verb tense
  - Fix up and downstream metrics output for proxy
  - Issue 40095: uTLS for broker negotiation
  - Forward bridge fingerprint from client to broker (WIP, Issue 28651)
  - Issue 40104: Make it easier to configure proxy type
  - Remove version from ClientPollRequest
  - Issue 40124: Move tor-specific code out of library
  - Issue 40115: Scrub pt event logs
  - Issue 40127: Bump webrtc and dtls library versions
  - Bump version of webrtc and dtls to fix dtls CVEs
  - Issue 40141: Ensure library calls of events can be scrubbed

Sponsored by:   TorBSD Diversity Project (TDP)
Sponsored by:   The Tor Project