Read aloud skips segments on Safari

**Description**

On Safari, when a read aloud session is live and a user clicks the button to skip ahead ~10 seconds, the highlight bumps to the next segment, the reader starts reading it, then the highlight jumps ahead one more segment. This means that when skipping, the reader is no longer reading the highlighted section, but the one before.

When the reader gets to the end of its section, it starts the next, and the highlighted section jumps forward again so it is constantly ahead.

Consecutive clicks of the skip ahead button result in the reader starting to read only every other segment.

**Evidence / Screenshot (if possible)**

video: https://www.dropbox.com/s/ni8m0jbib5rjiv3/safari_bookreader_skipping_bug.mp4?dl=0
sample book used (issue confirmed with multiple books): https://archive.org/details/TheMindIlluminatedByCuladasaJohnYatesPh.D.MatthewImmergutJeremyGraves2017/page/n11/mode/2up

**Expectation**

Complete sync between reader and highlight in Safari as in Chrome

**Context**

macOS Monerey 12.3.1 (21E258), Safari Version 15.4 (17613.1.17.1.13)

**Proposal & Constraints**

> What is the proposed solution / implementation? Is there a precedent of this approach succeeding elsewhere?

**Stakeholders**

> @-tag any stakeholders of this bug