Auto merge of #4569 - james9909:add-comparison-chain, r=oli-obk

Add a new lint for comparison chains

changelog: Adds a new lint: `comparison_chain`.

`comparison_chain` lints all `if` conditional chains where all the conditions are binary comparisons on the same two operands and will suggest a rewrite with `match`.

Closes #4531.

diff --cc clippy_lints/src/copies.rs
Simple merge

diff --cc clippy_lints/src/utils/mod.rs
Simple merge