Bump env_logger to 0.10.

[monaka]

Description

Notes to the reviewers

This will reduce using atty that is unmainted.
See also: https://rustsec.org/advisories/RUSTSEC-2021-0145

Changelog notice

Checklists

All Submissions:

• I've signed all my commits
• I followed the contribution guidelines
• I ran cargo fmt and cargo clippy before committing

New Features:

• I've added tests for the new feature
• I've added docs for the new feature

Bugfixes:

• This pull request breaks the existing API
• I've added tests to reproduce the issue which are now passing
• I'm linking the issue being fixed by this PR

[tnull]

Unfortunately, env_logger 0.10 seems to require rustc 1.60 which doesn't meet MSRV policy. Up to 0.9.3, env_logger only required rustc 1.41.0, which may therefore be an option. However, this version is still dependent on atty, so at least for the given reason it doesn't make much sense to bump it to 0.9.3 either.

[evanlinjin]

Thank you for this PR, unfortunately it doesn't seem possible due to MSRV requirements (thanks to @tnull for pointing this out). Closing for now.

[apoelstra]

If the dep can really be bumped with no changes to the codebase, it may be possible to provide a ranged version that covers multiple major versions.

[notmandatory]

@evanlinjin we should be able to bump env_logger to 0.10 and just cargo update --precise it back to 0.7 in CI for verifying build/tests with our MSRV (1.57), as in #1046.

[evanlinjin]

@evanlinjin we should be able to bump env_logger to 0.10 and just cargo update --precise it back to 0.7 in CI for verifying build/tests with our MSRV (1.57), as in #1046.

If we set env_logger = "0.10", version 0.7 would not be compatible: https://doc.rust-lang.org/cargo/reference/resolver.html#semver-compatibility

We need to see whether setting a range (from 0.7 to 0.10) does not break builds at any version of env_logger (as @apoelstra suggested).

@monaka Sorry I closed the PR too early. Seems like there is a lot more options to explore. I'll create a ticket.

Edit: Ticket created (#1067).