Rollup merge of #5412 - dtolnay:tostring, r=flip1995

Downgrade inefficient_to_string to pedantic

From the [documentation](https://rust-lang.github.io/rust-clippy/master/index.html#inefficient_to_string):

> ```diff
> - ["foo", "bar"].iter().map(|s| s.to_string());
>
> + ["foo", "bar"].iter().map(|&s| s.to_string());
> ```

I feel like saving 10 nanoseconds from the formatting machinery isn't worth asking the programmer to insert extra `&` / `*` noise in the *vast* majority of cases. This is a pedantic lint.

changelog: Remove inefficient_to_string from default set of enabled lints

0 files changed, 0 insertions, 0 deletions