Use the same err on the left hand side

---

examples/redefine-variable/redefine_variable.go

package main

import (
    "fmt"
    "os"
    "strconv"
)

func main() {
    a, err := strconv.Atoi("23")
    fmt.Println(a)
    if err != nil {
        os.Exit(1)
    }
    b, err := strconv.ParseFloat("3.4", 64)
    if err != nil {
        os.Exit(1)
    }
    fmt.Println(b)
}

23
3.4