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

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https://hg.mozilla.org/integration/gaia-central/rev/4f5a41b7971b
Author: Marcus Cavanaugh <m@mcav.com>
Desc: Merge pull request #20628 from mcav/tab-css

Bug 1017398 - [B2G][Clock] Function tab color does not fit specification... r=millermedeiros

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https://hg.mozilla.org/integration/gaia-central/rev/4b5432fd8afd
Author: Marcus Cavanaugh <m@mcav.com>
Desc: Bug 1017398 - [B2G][Clock] Function tab color does not fit specification.
Bumping manifests a=b2g-bump