tracing-log 0.2.0

This release contains two breaking changes: the removal of the env_logger
and trace_logger features. Below are the suggested migration paths:

• env_logger: users should use tracing_subscriber::fmt::Subscriber
  or tracing_subscriber::fmt::Layer with the Targets or
  EnvFilter filters instead.
• trace_logger: users should use the tracing crate's
  "log" feature flag instead.

Breaking Changes

• Remove deprecated env_logger feature. This removes the dependency
  on the unmaintained atty crate, resolving the security advisory
  GHSA-g98v-hv3f-hcfr/RUSTSEC-2021-0145. (#2771)
• Remove deprecated trace_logger feature. (#2771)