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

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https://hg.mozilla.org/integration/gaia-central/rev/3e01eab0c383
Author: Douglas Sherk <github@sherk.me>
Desc: Merge pull request #17957 from DouglasSherk/991865-voicemail-silent-fail

Bug 991865 - [System][Dialer] Display an error message when calling voicemail fails due to no number set. r=rik

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https://hg.mozilla.org/integration/gaia-central/rev/858cd1ede9f3
Author: DouglasSherk <github@sherk.me>
Desc: Bug 991865 - [System][Dialer] Display an error message when calling voicemail fails due to no number set. r=rik
Bumping manifests a=b2g-bump