Document why we can't deny needless_continue

Author: sbernauer

Cargo.toml

@@ -103,8 +103,9 @@ cast_possible_truncation = "allow"
 float_cmp = "allow"
 cast_sign_loss = "allow"
 cast_precision_loss = "allow"
-needless_continue = "allow"
 unchecked_time_subtraction = "allow"
+# We should be able to deny this, but it lint's on code generated by darling, raised https://github.com/TedDriggs/darling/pull/429
+needless_continue = "allow"
 
 # Additional nursery lints we enforce
 use_self = "deny"