Returns the HAR Page Load Time

*Example:*
| New HAR             | myHARFile              |
| Navigate To         |                        |
| Get HAR             |                        |
| Save HAR            |                        |
| ${harPageLoadTime}= | Get HAR Page Load Time |


For integrated HAR support, the following properties should be enabled/defined
*jspringbot.properties*
selenium.browser.mob.proxy.enabled=true
selenium.browser.mob.proxy.har.save.dir=/Users/shielabuitizon/workspace/jspringbot-selenium/target/robotframework-reports/har

!!! Note:
* Should not be used with "Proxy Properties" and "Saucelabs Properties" since HAR support is already using Selenium Proxy

