AccountSet: Fixed example code in documentation that was adding wrong filter key 'protocol'.
AccountSet: Fixed example code in documentation that was adding wrong filter key 'protocol'.

TelepathyQt/telepathy-qt,detrout/telepathy-qt,anantkamath/telepathy-qt,anantkamath/telepathy-qt,TelepathyIM/telepathy-qt,TelepathyQt/telepathy-qt,TelepathyIM/telepathy-qt,TelepathyIM/telepathy-qt,special/telepathy-qt-upstream,TelepathyQt/telepathy-qt,freedesktop-unofficial-mirror/telepathy__telepathy-qt,detrout/telepathy-qt,freedesktop-unofficial-mirror/telepathy__telepathy-qt4,freedesktop-unofficial-mirror/telepathy__telepathy-qt,special/telepathy-qt-upstream,special/telepathy-qt-upstream,tiagosh/telepathy-qt,TelepathyQt/telepathy-qt,TelepathyIM/telepathy-qt,TelepathyIM/telepathy-qt,tiagosh/telepathy-qt,detrout/telepathy-qt,anantkamath/telepathy-qt,freedesktop-unofficial-mirror/telepathy__telepathy-qt4,tiagosh/telepathy-qt,tiagosh/telepathy-qt,freedesktop-unofficial-mirror/telepathy__telepathy-qt4,freedesktop-unofficial-mirror/telepathy__telepathy-qt,freedesktop-unofficial-mirror/telepathy__telepathy-qt,freedesktop-unofficial-mirror/telepathy__telepathy-qt4