changeBootstrapClass(className, newValue) {
    const boostrapClass = this.getBootstrapColumnClass(className)
    return className.replace(boostrapClass, `${this.getBootstrapColumnPrefix(className)}-${newValue}`)
  }
Example className of 'row row-1 col-md-6' would be changed for 'row row-1 col-md-4' where 4 is the newValue
@param {string} className
@param {number} newValue
@returns {string}