/**
 * Update Chart.js version in the HTML report files.
 *
 * @param reportDir
 * @param {string} oldVersion - old Chart.js version (ex: '2.5.0')
 * @param {string} newVersion - new Chart.js version (ex: '2.6.0')
 */
export declare function updateChartJsVersion(reportDir: string, oldVersion: any, newVersion: any): void;