[web] Disable pointer events on timestamp tooltip
[web] Disable pointer events on timestamp tooltip

Summary: I noticed this while reviewing D59. If the tooltip renders over the pointer when it first renders, it will trigger `onMouseOut`/`onMouseLeave` and hide the tooltip, leading to an infinite loop

Reviewers: KatPo, palys-swm

Reviewed By: KatPo

Subscribers: zrebcu411, Adrian

Differential Revision: https://phabricator.ashoat.com/D78

Ashoat/squadcal,Ashoat/squadcal,Ashoat/squadcal,Ashoat/squadcal,Ashoat/squadcal,Ashoat/squadcal,Ashoat/squadcal