Bumping gaia.json for 3 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-2_1/rev/61544c197105
Author: Eitan Isaacson <eitan@monotonous.org>
Desc: Bug 1055355 - Make recipient field and suggestions screen reader friendly.

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https://hg.mozilla.org/integration/gaia-2_1/rev/c3ae47b654bc
Author: Yura Zenevich <yzenevich@mozilla.com>
Desc: Bug 1063039 - update playing icon only if the audio channel actually changes.

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https://hg.mozilla.org/integration/gaia-2_1/rev/503850110c5e
Author: TheoChevalier <theo.chevalier11@gmail.com>
Desc: Bug 1062845 - Done button when picking a song in Ringtones manager is hardcoded
Bumping manifests a=b2g-bump