Fix typo in trace event name mapping.
Fix typo in trace event name mapping.

See https://github.com/WPO-Foundation/webpagetest/blob/0894ec24a7788354db3b92265842f25cac746947/www/breakdownTimeline.php#L81

sitespeedio/browsertime,sitespeedio/browsertime,sitespeedio/browsertime,sitespeedio/browsertime,tobli/browsertime