Bumping gaia.json for 2 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/a1cb484514b6
Author: Zibi Braniecki <zbigniew.braniecki@gmail.com>
Desc: Merge pull request #18882 from zbraniecki/999195-cleanup-mozl10n-emergency-call

999195 cleanup mozl10n emergency call. r=rik

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https://hg.mozilla.org/integration/gaia-central/rev/d6d4f7838822
Author: Zbigniew Braniecki <gandalf@mozilla.com>
Desc: Bug 999195 - Clean up bootstrap mozL10n API use in Emergency Call. r=gweng
Bumping manifests a=b2g-bump