fix(page): fix missing awaits in mouse.click #4536

[pqvst]

Lack of await causes dangling promises, which lead to unhandled rejections that cannot be caught if these calls fail (e.g. if the page is closed). See issue #4536 for details.

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[pqvst]

I signed it!

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[aslushnikov]

We sit with @JoelEinbinder and ended up with this. 🤷‍♂️

[aslushnikov]

I'll follow-up with a test and a firefox-fix.

edit: follow-up is #4561