refactor: use slice for function parameter

Accepting a slice is more flexible and idiomatic than a vector reference (@ljedrz)

Co-authored-by: ljedrz <3750347+ljedrz@users.noreply.github.com>

Author: hiratara

src/term.rs

@@ -690,7 +690,7 @@ fn base26_encode(mut n: u32) -> String {
 
 fn show_precedence_cla(
     ctx: &Context,
-    binder_names: &Vec<String>,
+    binder_names: &[String],
     term: &Term,
     context_precedence: usize,
     depth: u32,