Update top crate list

[konnorandrews]

The top crate list needs to be updated to stop building with nightly from showing the new rust-lang/rust#102635 warning. See attached image for how the warning shows up on the playground.

The crate at issue is log4rs which has moved to a different dependency that does not trigger the warning estk/log4rs#247. This has been confirmed as resolving the issue by updating log4rs to version 1.2.0.

I have tested a local copy of the playground with just running the top-crates binary and the issue was resolved.

Also of note, the https://github.com/kangalioo/rustbot bot, used by the community Discord, uses nightly by default so this warning shows on all uses by default.