Add internal lint to check for slow symbol comparisons See the conversation on [Zulip](https://rust-lang.zulipchat.com/#narrow/stream/257328-clippy/topic/Checking.20a.20Symbol.20is.20equal.20to.20a.20string.20literal). changelog: none
Add internal lint to check for slow symbol comparisons See the conversation on [Zulip](https://rust-lang.zulipchat.com/#narrow/stream/257328-clippy/topic/Checking.20a.20Symbol.20is.20equal.20to.20a.20string.20literal). changelog: none