Fix the extracted name of some clone methods

[sonmarcho]

This is related to #375 (comment)
The following code:

#[derive(Clone)]
pub struct Record {
    age: u32,
    zip: u32,
    salary: u32,
}

extracted to:

... -- Omitting the struct

def ClonekanonRecord.clone (self : Record) : Result Record :=
  let i := core.clone.CloneU32.clone self.age
  let i1 := core.clone.CloneU32.clone self.zip
  let i2 := core.clone.CloneU32.clone self.salary
  Result.ok { age := i, zip := i1, salary := i2 }

while it was supposed to extract to:

def CloneissueRecord.clone (self : Record) : Result Record :=
  let i := core.clone.impls.CloneU32.clone self.age
  let i1 := core.clone.impls.CloneU32.clone self.zip
  let i2 := core.clone.impls.CloneU32.clone self.salary
  Result.ok { age := i, zip := i1, salary := i2 }