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

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https://hg.mozilla.org/integration/gaia-central/rev/7172e2aa25e6
Author: Ian Liu <iliu@mozilla.com>
Desc: Merge pull request #21571 from ian-liu/bluetooth/bug1029037_pairing_dialog_is_closing_abnormally_while_screen_is_transitioning

Bug 1029037 - [B2G][Bluetooth]Screen transitioning while reciving a pairrequest will not close the pairing dialog normally. r=@arthur

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https://hg.mozilla.org/integration/gaia-central/rev/ba5282d39981
Author: ian-liu <iliu@mozilla.com>
Desc: Bug 1029037 - [B2G][Bluetooth]Screen transitioning while reciving a pair request will not close the pairing dialog normally.
Bumping manifests a=b2g-bump