Rollup merge of rust-lang#161592 - pacak:change-pattern-tests, r=nia-e

core: refactor tests/pattern.rs tests

Firstly, combine functions and results lists into a single list with `'function => result' `pairs.  This makes it easier to match function with its result.

Secondly, eliminate `InRange` step so that it's easier to notice series of matches or rejects.

I also added a variant to `test_stress_indices` that matches stuff with `|_| true` which wasn't covered.

This commit is extracted from rust-lang#160971

Author: Zalathar