`flycheck-rust-cargo-has-command-p` returns `nil` incorrectly

[PatrickNorton]

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Checklist

• I have checked existing issues for potential duplicates before creating this one.
• I have read the Troubleshooting guide.

Bug description

Running (flycheck-rust-cargo-has-command-p "run") (or any other Cargo command) returns nil when it should return t. This is because flycheck-rust-cargo-has-command-p uses cargo --list as a basis, which returns descriptions for each subcommand (ever since rust-lang/cargo#9848). This means (member command ...) returns nil.

Steps to reproduce

Steps to reproduce the behavior:

1. Run (flycheck-rust-cargo-has-command-p "run") with a sufficiently recent (>= 1.56) version of Cargo installed.
2. Observe that it returns nil

• I have read https://emacs.stackexchange.com/questions/28429/how-do-i-troubleshoot-emacs-problems

Expected behavior

The command should return t when the command is installed

Emacs configuration:

• Plain Emacs / Custom configuration
• Spacemacs
• Doom Emacs
• Other shared configuration

[jimenezrick]

This patch works for me using plain Emacs (with my custom config):
https://github.com/flycheck/flycheck/pull/1917/files