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

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https://hg.mozilla.org/integration/gaia-central/rev/ba3a558fbb2d
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Merge pull request #14656 from etiennesegonzac/bug-937505-keypad-latency

Bug 937505 - Dialer Keypad - Touch Handling - Doing the expensive work after a tick to reduce the audio tone latency. r=rik

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https://hg.mozilla.org/integration/gaia-central/rev/7c24c414a435
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Bug 937505 - Dialer Keypad - Touch Handling - Doing the expensive work
after a tick to reduce the audio tone latency.
r=rik