Prohibit methods that can leak data

seq_join won't be happy with them anymore

.clippy.toml

@@ -2,4 +2,8 @@
 disallowed-methods = [
   { path = "futures::future::join_all", reason = "We don't have a replacement for this method yet. Consider extending `SeqJoin` trait." },
   { path = "futures::future::try_join_all", reason = "Use Context.try_join instead." },
+  { path = "std::boxed::Box::leak", reason = "Not running the destructors on futures created inside seq_join module will cause UB in IPA. Make sure you don't leak any of those." },
+  { path = "std::mem::forget", reason = "Not running the destructors on futures created inside seq_join module will cause UB in IPA. Make sure you don't leak any of those." },
+  { path = "std::mem::ManuallyDrop::new", reason = "Not running the destructors on futures created inside seq_join module will cause UB in IPA. Make sure you don't leak any of those." },
+  { path = "std::vec::Vec::leak", reason = "Not running the destructors on futures created inside seq_join module will cause UB in IPA. Make sure you don't leak any of those." },
 ]