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

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https://hg.mozilla.org/integration/gaia-central/rev/de5a67ae6bbf
Author: Michael Henretty <michael.henretty@gmail.com>
Desc: Merge pull request #13494 from mikehenrty/bug-882186-mvp

Bug 882186 - add basic net_error.html functionality, r=vingtetun

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https://hg.mozilla.org/integration/gaia-central/rev/883160c71c3e
Author: Michael Henretty <michael.henretty@gmail.com>
Desc: Bug 882186 - add basic net_error.html functionality