log: remove deprecated env_logger and trace_logger APIs (tokio-rs…

…#2771)

Removing the `env_logger` feature in order to address GHSA-g98v-hv3f-hcfr.

In addition, this PR also removes the deprecated `trace_logger` module, in
preparation for an upcoming v0.2.0 of `tracing-log`.

For additional details on the approach, please refer to tokio-rs#2750. Note that this
PR depends on tokio-rs#2770, so this PR will temporarily have more commits 
than intended. 
---------

Co-authored-by: Eliza Weisman <[email protected]>

tracing-log/README.md

@@ -43,8 +43,6 @@ This crate provides:
 - [`AsTrace`] and [`AsLog`] traits for converting between `tracing` and `log` types.
 - [`LogTracer`], a [`log::Log`] implementation that consumes [`log::Record`]s
   and outputs them as [`tracing::Event`]s.
-- An [`env_logger`] module, with helpers for using the [`env_logger` crate]
-  with `tracing` (optional, enabled by the `env_logger` feature).
 
 [`tracing`]: https://crates.io/crates/tracing
 [`log`]: https://crates.io/crates/log

tracing-log/src/lib.rs

@@ -13,8 +13,6 @@
 //! - [`AsTrace`] and [`AsLog`] traits for converting between `tracing` and `log` types.
 //! - [`LogTracer`], a [`log::Log`] implementation that consumes [`log::Record`]s
 //!   and outputs them as [`tracing::Event`].
-//! - An [`env_logger`] module, with helpers for using the [`env_logger` crate]
-//!   with `tracing` (optional, enabled by the `env-logger` feature).
 //!
 //! *Compiler support: [requires `rustc` 1.63+][msrv]*
 //!
@@ -70,8 +68,6 @@
 //!
 //! # Feature Flags
 //! * `log-tracer`: enables the `LogTracer` type (on by default)
-//! * `env_logger`: enables the `env_logger` module, with helpers for working
-//!   with the [`env_logger` crate].
 //! * `interest-cache`: makes it possible to configure an interest cache for
 //!   logs emitted through the `log` crate (see [`Builder::with_interest_cache`]); requires `std`
 //!