let targetEL = document.querySelector(".icon-listing")

let arrayI = targetEL.querySelectorAll("i")

let result = []
for (let i = 0; i < arrayI.length; i++) {

    let item = ""
    for (let j = 0; j < arrayI[i].classList.length; j++) {
        item += `${arrayI[i].classList[j]} `
    }

    result.push(item)
}

console.log(result)