Update ouroboros following RUSTSEC-2023-0042

[nicochatzi]

Thank you for helping out with embedded-graphics-simulator development! Please:

• Check that you've added passing tests and documentation
• Add an example where applicable
• Add a CHANGELOG.md entry in the Unreleased section under the appropriate heading (Added, Fixed, etc) if your changes affect the public API
• Run rustfmt on the project
• Run just build (Linux/macOS only) and make sure it passes. If you use Windows, check that CI passes once you've opened the PR.

PR description

Quick update to ouroboros 0.15.5 -> 0.17.2 (latest). RUSTSEC_2023-0042 has flagged versions <0.16.0 as unsound.

I can update the other dependencies if you think it's worth doing as part of this PR.
I quickly scanned the CHANGELOG and it doesn't seem like you mark dependency updates (other than embedded-graphics) so I did not add this change to the log.

(edit) Rust MSRV

It looks CI is failing because half v2.3.1 requires Rust version >= v1.70.0. Seeing as jamwaffles provides the circleci-embedded-graphics container with rust version 1.71.1, I've bumped the MSRV to that.

[jamwaffles]

Thanks! Yeah the MSRV bump makes sense, and puts this crate in line with embedded-graphics itself.