Any way to run `clippy` not only on save?

### Feature description

Is there a way to run "flychecks" on demand (at least in Normal mode)?
I don't see any mention of it in the documentation

Related rust-analyzer PR and rust-lang issue: https://github.com/rust-lang/rust-analyzer/issues/13125, https://github.com/rust-lang/rust-analyzer/pull/13785