update if skip silence button is shown on seek

[Mjaethers]

Motivation and Context

Fixes #1223.
When jumping backward or forwards in the video player the "Skip pause" button is not updated, meaning that pressing it after jumping forwards could take you back again. Or when jumping into a silent segment it is not possible to immediately jump to the end of it without first unpausing.

Description

The function that checks whether this button should be displayed is called whenever the user seeks (jumps backwards or forwards)

Steps for Testing

Prerequisites:

• 1 Stream

1. Log in
2. Navigate to a Stream with silences
3. Pause the Stream in a silent segment
4. Jump past it, notice the "Skip pause" button vanishes
5. Jump back into a silent segment, notice the button reappears

Screenshots

untitled.mp4

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