fix(screenshare): constraints use desktopSharingFrameRate option
fix(screenshare): constraints use desktopSharingFrameRate option

Actually pass in the option to getTrackSSConstraints so it gets
applied to the desktop track.

jitsi/lib-jitsi-meet,jiyeyuran/lib-jitsi-meet,damencho/lib-jitsi-meet,jitsi/lib-jitsi-meet