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

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https://hg.mozilla.org/integration/gaia-central/rev/269c56ee3c58
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #15991 from zacc/bug_967908

Bug 967908 Fix timing in test_sms_contact_input_validation.py

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https://hg.mozilla.org/integration/gaia-central/rev/fb17eadc4065
Author: Zac Campbell <zcampbell@mozilla.com>
Desc: Bug 967908 - Repair test_sms_contact_input_validation r=zac
Bumping manifests a=b2g-bump