Fixes #5405: redundant clone false positive with arrays

[rabisg0]

Check whether slice elements implement Copy before suggesting to drop
the clone method

changelog: add a check for slice indexing on redundant_clone lint

[phansch]

Thanks for the PR!

You're currently getting a dead_code error on CI - You can either call the issue_5405 function from main or add an #![allow(dead_code)] to the top of the ui test file to fix it.

[rabisg0]

Hey @phansch
Thanks for looking into it. I fixed that problem but Im running into a different issue w.r.t. fix suggestion.
Will update this patch once I fix that

[phansch]

@bors r+ thanks!

[bors]

📌 Commit ab3946d has been approved by phansch

[bors]

⌛ Testing commit ab3946d with merge 74e9256...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: phansch
Pushing 74e9256 to master...