Bumping gaia.json for 3 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/ab48cd170930
Author: Gareth Aye <gaye@mozilla.com>
Desc: Merge pull request #21277 from gaye/calendar-server-test-calendar-or-user-name

Allow username to be different from calendar name in server tests

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https://hg.mozilla.org/integration/gaia-central/rev/004d82be3f8e
Author: gaye <gaye@mozilla.com>
Desc: Allow username to be different from calendar name in server tests

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https://hg.mozilla.org/integration/gaia-central/rev/341fe9c32e28
Author: Gabriele Svelto <gsvelto@mozilla.com>
Desc: Bug 1016885 - Send a notification instead of displaying the dialer when receiving an unsolicited USSD notification r=etienne

b2g/config/gaia.json

@@ -4,6 +4,6 @@
         "remote": "", 
         "branch": ""
     }, 
-    "revision": "bf10f526c129670add7629c78ed5f5bcc95f2802", 
+    "revision": "ab48cd1709309a7c506bd601ea98455e02ea89cc", 
     "repo_path": "/integration/gaia-central"
 }