Use assert!(foo) instead of assert_eq!(foo, true)

It is redundant to pass true/false to `assert_eq!` since `assert!`
already asserts true/false.

This may, however, be controversial if someone thinks that

```
    assert_eq!(foo, false);
```

is more clear than

```
    assert!(!foo);
```

Use `assert!` directly instead of `assert_eq!` with true/false argument.

src/wallet/mod.rs

@@ -3514,7 +3514,7 @@ pub(crate) mod test {
         let (mut psbt, _) = builder.finish().unwrap();
 
         let finalized = wallet.sign(&mut psbt, Default::default()).unwrap();
-        assert_eq!(finalized, true);
+        assert!(finalized);
 
         let extracted = psbt.extract_tx();
         assert_eq!(extracted.input[0].witness.len(), 2);
@@ -3531,7 +3531,7 @@ pub(crate) mod test {
         let (mut psbt, _) = builder.finish().unwrap();
 
         let finalized = wallet.sign(&mut psbt, Default::default()).unwrap();
-        assert_eq!(finalized, true);
+        assert!(finalized);
 
         let extracted = psbt.extract_tx();
         assert_eq!(extracted.input[0].witness.len(), 2);
@@ -3548,7 +3548,7 @@ pub(crate) mod test {
         let (mut psbt, _) = builder.finish().unwrap();
 
         let finalized = wallet.sign(&mut psbt, Default::default()).unwrap();
-        assert_eq!(finalized, true);
+        assert!(finalized);
 
         let extracted = psbt.extract_tx();
         assert_eq!(extracted.input[0].witness.len(), 2);
@@ -3565,7 +3565,7 @@ pub(crate) mod test {
         let (mut psbt, _) = builder.finish().unwrap();
 
         let finalized = wallet.sign(&mut psbt, Default::default()).unwrap();
-        assert_eq!(finalized, true);
+        assert!(finalized);
 
         let extracted = psbt.extract_tx();
         assert_eq!(extracted.input[0].witness.len(), 2);
@@ -3583,7 +3583,7 @@ pub(crate) mod test {
         let (mut psbt, _) = builder.finish().unwrap();
 
         let finalized = wallet.sign(&mut psbt, Default::default()).unwrap();
-        assert_eq!(finalized, true);
+        assert!(finalized);
 
         let extracted = psbt.extract_tx();
         assert_eq!(extracted.input[0].witness.len(), 2);
@@ -3603,7 +3603,7 @@ pub(crate) mod test {
         assert_eq!(psbt.inputs[0].bip32_derivation.len(), 0);
 
         let finalized = wallet.sign(&mut psbt, Default::default()).unwrap();
-        assert_eq!(finalized, true);
+        assert!(finalized);
 
         let extracted = psbt.extract_tx();
         assert_eq!(extracted.input[0].witness.len(), 2);