doc: Fix media::{get,set}_subtitle_uri() symbol names
doc: Fix media::{get,set}_subtitle_uri() symbol names

At first, those symbols were called {get,set}_subtitles_uri() but were
renamed to {get,set}_subtitle_uri() without updating the
clutter-section.txt file.

This fix makes gtk-doc document those symbols again.

nobled/clutter,djdeath/clutter,GNOME/clutter,djdeath/clutter-multithreaded,djdeath/clutter,ebassi/clutter,Distrotech/clutter,ebassi/clutter,GNOME/clutter,djdeath/clutter,jigpu/clutter,jigpu/clutter,spatulasnout/clutter,collects/clutter,kerrickstaley/clutter-vala,heysion/clutter-clone,GNOME/clutter,collects/clutter,nobled/clutter,kerrickstaley/clutter-vala,dlespiau/clutter,ebassi/clutter,nobled/clutter,ebassi/clutter,spatulasnout/clutter,spatulasnout/clutter,djdeath/clutter,Distrotech/clutter,djdeath/clutter-android,dlespiau/clutter,heysion/clutter-clone,Distrotech/clutter,kerrickstaley/clutter-vala,djdeath/clutter-multithreaded,heysion/clutter-clone,rkudiyarov/clutter_osx,djdeath/clutter,rkudiyarov/clutter_osx,jigpu/clutter,djdeath/clutter-android,ebassi/clutter,jigpu/clutter,dlespiau/clutter,djdeath/clutter-android,djdeath/clutter,collects/clutter,collects/clutter,spatulasnout/clutter,rkudiyarov/clutter_osx,Distrotech/clutter,jigpu/clutter,heysion/clutter-clone,rkudiyarov/clutter_osx,spatulasnout/clutter,djdeath/clutter-multithreaded,kerrickstaley/clutter-vala,djdeath/clutter-multithreaded,djdeath/clutter-android,GNOME/clutter,Distrotech/clutter,djdeath/clutter-android,GNOME/clutter,jigpu/clutter,collects/clutter,heysion/clutter-clone,Distrotech/clutter