Silence two misguided clippy warnings

src/lab.rs

@@ -162,6 +162,7 @@ pub fn test_unmutated_then_all_mutants(
 ///
 /// The [BuildDir] is passed as mutable because it's for the exclusive use of this function for the
 /// duration of the test.
+#[allow(clippy::needless_pass_by_ref_mut)]
 fn test_scenario(
     tool: &dyn Tool,
     build_dir: &mut BuildDir,

src/process.rs

@@ -158,6 +158,7 @@ impl Process {
 }
 
 #[cfg(unix)]
+#[allow(clippy::needless_pass_by_ref_mut)] // To match Windows
 fn terminate_child_impl(child: &mut Popen) -> Result<()> {
     use nix::errno::Errno;
     use nix::sys::signal::{killpg, Signal};