Add new lint might_panic

[cocodery]

fixes #issue11808

This lint check accessing array or slice with index but don't know whether this index is legal.

For example, the code

let numbers = &[4, 7, 3];
let _my_number = numbers[5];

can be written as

let numbers = &[4, 7, 3];
let Some(_my_number) = numbers.get(5) else { panic!(); }

Besides, if you declare my_number with its type i32,

let numbers = &[4, 7, 3];
let _my_number : i32 = numbers[5];

it can be written as

let numbers = &[4, 7, 3];
let Some(_my_number): Option<&i32> = numbers.get(5) else { panic!() };

This lint can help programmer to locate where you access array out of boundary easilier, and can write their handler.

changelog: add new lint might_panic

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @xFrednet (or someone else) soon.

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[bors]

☔ The latest upstream changes (presumably #11597) made this pull request unmergeable. Please resolve the merge conflicts.

[rustbot]

There are merge commits (commits with multiple parents) in your changes. We have a no merge policy so these commits will need to be removed for this pull request to be merged.

You can start a rebase with the following commands:

$ # rebase
$ git rebase -i master
$ # delete any merge commits in the editor that appears
$ git push --force-with-lease

The following commits are merge commits:

• 432a8d0

[xFrednet]

Hey @cocodery, I think you can leave this PR until the discussion in the issue has been solved. If you rebase now, it's likely to be broken again, by the time we came to a conclusion. You can maybe pickup another issue, with the good-first-issue label :)

[cocodery]

Hey @cocodery, I think you can leave this PR until the discussion in the issue has been solved. If you rebase now, it's likely to be broken again, by the time we came to a conclusion. You can maybe pickup another issue, with the good-first-issue label :)

Hi, thanks for your advice! I'll waiting for you conclusion.
I'm fixing another issue currently. They help me a lot with learning Rust!

[xFrednet]

I'm closing this PR due to the reasons stated in the issue. @cocodery Thank you for trying to implement this issue! If you have any questions, you're welcome to reach out.