fixed puppeteer tests

Author: DavertMik

lib/element/WebElement.js

@@ -249,6 +249,7 @@ class WebElement {
       case 'webdriver':
         return this.element.setValue(text)
       case 'puppeteer':
+        await this.element.evaluate(el => { el.value = '' })
         return this.element.type(text, options)
       default:
         throw new Error(`Unsupported helper type: ${this.helperType}`)