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

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https://hg.mozilla.org/integration/gaia-central/rev/c2ddcb795e75
Author: EragonJ <eragonj@eragonj.me>
Desc: Merge pull request #15959 from EragonJ/bug-967708

Bug 967708 - [B2G][l10n][Settings] German: "Change PIN" doesn't use loca...

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https://hg.mozilla.org/integration/gaia-central/rev/8ec6f75ad859
Author: EragonJ <eragonj@eragonj.me>
Desc: Bug 967708 - [B2G][l10n][Settings] German: "Change PIN" doesn't use localization
Bumping manifests a=b2g-bump