This PR directly addresses the issue raised in #23282 where Deno panics
if `deno coverage` is called with `--include` regex that returns no
matches.
I've opted not to change the return value of `collect_summary` for
simplicity and return an empty `HashMap` instead
1. Generally we should prefer to use the `log` crate.
2. I very often accidentally commit `eprintln`s.
When we should use `println` or `eprintln`, it's not too bad to be a bit
more verbose and ignore the lint rule.
