e966335447 chore: remove explicit into iteration (jike)
Pull request description:
```
warning: it is more concise to loop over containers instead of using explicit iteration methods
--> bitcoin/src/psbt/serialize.rs:209:21
|
209 | for cnum in self.1.into_iter() {
| ^^^^^^^^^^^^^^^^^^ help: to write this more concisely, try: `&self.1`
```
ACKs for top commit:
Kixunil:
ACK e966335447
apoelstra:
ACK e9663354476b0b9b2ec52ce034de5ab9223f9d29; successfully ran local tests
Tree-SHA512: 32fced1a5aba2caa6e48a2e586bf00dcf3d4b82b6b530d9c7f535b530737a40e24d5c05a7cea40747df4c7c4698ec141683b9416583b185b1ff6461f3c8f667f