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

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https://hg.mozilla.org/integration/gaia-central/rev/67d1ce647542
Author: steveck-chung <schung@mozilla.com>
Desc: Merge pull request #25838 from steveck-chung/system-cb-cmas-filter

Bug 1091751 - Sending two kinds of message for cellbroadcast-received, r=kgrandon

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https://hg.mozilla.org/integration/gaia-central/rev/6c2e01ba68f1
Author: Steve Chung <schung@mozilla.com>
Desc: Bug 1091751 - Sending two kinds of message for cellbroadcast-received, r=kgrandon
Bumping manifests a=b2g-bump