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

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https://hg.mozilla.org/integration/gaia-central/rev/690d2ea2241b
Author: Rex KM Lee <rexboy@mozilla.com>
Desc: Merge pull request #13652 from rexboy7/fix-bug933576

Bug 933576 - [Dialer] (regression) Call screen should be shown when ente...

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https://hg.mozilla.org/integration/gaia-central/rev/a8eb679f6144
Author: Rex Lee <rexboy@mozilla.com>
Desc: Bug 933576 - [Dialer] (regression) Call screen should be shown when entering dialer app