Bumping gaia.json for 4 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/d82754b6fc1c
Author: Yura Zenevich <yura.zenevich@gmail.com>
Desc: Merge pull request #24942 from yzen/bug-1069197

Bug 1069197 - added screen reader support for the calendar for the month...

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https://hg.mozilla.org/integration/gaia-central/rev/38907948a073
Author: Yura Zenevich <yzenevich@mozilla.com>
Desc: Bug 1069197 - added screen reader support for the calendar for the month view. r=millermedeiros

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https://hg.mozilla.org/integration/gaia-central/rev/874521b9997f
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Merge pull request #25171 from pivanov/bug-1081657

Bug 1081657 - key.wav and special.wav does not sound different

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https://hg.mozilla.org/integration/gaia-central/rev/02c94f1f8b77
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Bug 1081657 - key.wav and special.wav does not sound different
Bumping manifests a=b2g-bump