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

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https://hg.mozilla.org/integration/gaia-central/rev/9b3047f19157
Author: Arthur Chen <crh0716@gmail.com>
Desc: Merge pull request #21746 from crh0716/1033207

Bug 1033207 - Do not override the custom apn settings r=jaoo

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https://hg.mozilla.org/integration/gaia-central/rev/3247e09e79b1
Author: Arthur Chen <crh0716@gmail.com>
Desc: Bug 1033207 - Do not overwrite the custom apn settings
Bumping manifests a=b2g-bump