address clippy warnings (#336)

src/circuit.rs

@@ -272,7 +272,7 @@ impl<'a, E: Engine, SC: StepCircuit<E::Base>> NovaAugmentedCircuit<'a, E, SC> {
   }
 }
 
-impl<'a, E: Engine, SC: StepCircuit<E::Base>> NovaAugmentedCircuit<'a, E, SC> {
+impl<E: Engine, SC: StepCircuit<E::Base>> NovaAugmentedCircuit<'_, E, SC> {
   /// synthesize circuit giving constraint system
   pub fn synthesize<CS: ConstraintSystem<<E as Engine>::Base>>(
     self,

src/provider/hyperkzg.rs

@@ -133,7 +133,7 @@ where
   }
 }
 
-impl<'a, 'b, E: Engine> Mul<&'b E::Scalar> for &'a Commitment<E>
+impl<'b, E: Engine> Mul<&'b E::Scalar> for &'_ Commitment<E>
 where
   E::GE: PairingGroup,
 {

src/provider/pedersen.rs

@@ -114,7 +114,7 @@ where
   }
 }
 
-impl<'a, 'b, E: Engine> Mul<&'b E::Scalar> for &'a Commitment<E>
+impl<'b, E: Engine> Mul<&'b E::Scalar> for &'_ Commitment<E>
 where
   E::GE: DlogGroup,
 {

src/r1cs/sparse.rs

@@ -129,7 +129,7 @@ pub struct Iter<'a, F: PrimeField> {
   nnz: usize,
 }
 
-impl<'a, F: PrimeField> Iterator for Iter<'a, F> {
+impl<F: PrimeField> Iterator for Iter<'_, F> {
   type Item = (usize, usize, F);
 
   fn next(&mut self) -> Option<Self::Item> {

src/spartan/macros.rs

@@ -14,7 +14,6 @@
 ///
 /// println!("{:?}", res); // Output: [6, 9, 12]
 /// ```
-
 #[macro_export]
 macro_rules! zip_with {
     // no iterator projection specified: the macro assumes the arguments *are* iterators