v0.48.0

Most notable changes:

• libp2p-swarm

  • Remove deprecated NetworkBehaviourEventProcess. See libp2p-swarm v0.38.0 changelog entry for
    migration path.

• 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!