Rust-libp2p v0.48.0 released

Most notable changes:

  • libp2p-swarm
  • libp2p-core
    • Make RSA keypair support optional. To enable RSA support, rsa feature should be enabled.
      See PR 2860.

  • libp2p-mdns
    • Allow users to choose between async-io and tokio runtime
      in the mdns protocol implementation. async-io is a default
      feature, with an additional tokio feature (see PR 2748)

For all other changes, see individual changelogs for details.

Thanks to the many folks involved!