docs: backtick parameter references in API comments

source/diagnostics/diagnostics.hon

@@ -28,7 +28,7 @@ Store :: struct { list arraylist.ArrayList(Diagnostic) }
 
 CapacityError :: enum { diagnostic_limit_reached }
 
-#! retains allocator for added diagnostics; the caller owns the returned Store.
+#! retains `allocator` for added diagnostics; the caller owns the returned Store.
 init proc(allocator mem.Allocator) Store {
     return Store{ list = arraylist.init(allocator) }
 }