new lint: `char_indices_as_byte_indices` (#13435)

Closes #10202.

This adds a new lint that checks for uses of the `.chars().enumerate()`
position in a context where a byte index is required and suggests
changing it to use `.char_indices()` instead.

I'm planning to extend this lint to also detect uses of the position in
iterator chains, e.g. `s.chars().enumerate().for_each(|(i, _)|
s.split_at(i));`, but that's for another time

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changelog: new lint: `chars_enumerate_for_byte_indices`

0 files changed, 0 insertions, 0 deletions