Add WP Rocket detection

[mostafa-hisham]

Detect websites that uses WP Rocket Plugin p.s. This is to make the Lighthouse Stack Pack work and detect the WP Rocket plugin https://github.com/GoogleChrome/lighthouse-stack-packs/pull/88

[connorjclark]

@mostafa-hisham can you also provide some example URLs that this detection should pass on?

[mostafa-hisham]

@connorjclark https://wp-rocket.me/ https://www.wpbeginner.com/ https://linuxhint.com/ https://wpml.org/ https://phoenixnap.com/

we can change the wp-rocket settings (enable/disable features) in the following website if you want to test certain condition https://imagify.rocketlabsqa.ovh/