Upgrade miniscript/bitcoin dependency

Upgrade:

- bitcoin to v0.31.0
- miniscript to v11.0.0

Note: The bitcoin upgrade includes improvements to the
`Transaction::weight()` function, it appears those guys did good, we
no longer need to add the 2 additional weight units "just in case".

example-crates/wallet_electrum/src/main.rs

@@ -99,7 +99,7 @@ fn main() -> Result<(), anyhow::Error> {
     let finalized = wallet.sign(&mut psbt, SignOptions::default())?;
     assert!(finalized);
 
-    let tx = psbt.extract_tx();
+    let tx = psbt.extract_tx()?;
     client.transaction_broadcast(&tx)?;
     println!("Tx broadcasted! Txid: {}", tx.txid());