function selectColor(taskName) {
    let color = taskNamesToColors.get(taskName)
    if (!color) {
        color = colors[colorIndex]
        colorIndex = (colorIndex + 1) % colors.length
        taskNamesToColors.set(taskName, color)
    }
    return color
}
Select a color from given task name.

@param {string} taskName - The task name.
@returns {function} A colorize function that provided by `chalk`