* chore: update to stable toolchain. apply clippy fixes & rustfmt
* Bump MSRV
* Try MSRV without the patch version
* fix: pin toolchain to MSRV
* trying again
* fix dead code warning
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Co-authored-by: Dan Sully <dsully@users.noreply.github.com>
As stated [here](https://doc.rust-lang.org/std/io/trait.BufRead.html#errors-1), `read_until` (and `read_line`) ignore Ctrl+C, so Topgrade does not respond to Ctrl+C in the retry prompt, and instead will exit only when enter is pressed after Ctrl+C. This is undesirable, so this pull request is a WIP until we find a solution.
