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

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https://hg.mozilla.org/integration/gaia-central/rev/efe61b291757
Author: Kyle Machulis <kyle@nonpolynomial.com>
Desc: Merge pull request #15825 from qdot/936037-pin-failure-in-ftu

Bug 963037 - Bring up PUK entry when PIN entry retries run out

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https://hg.mozilla.org/integration/gaia-central/rev/6ce8c896d1db
Author: Kyle Machulis <kyle@nonpolynomial.com>
Desc: Bug 963037 - Bring up PUK entry when PIN entry retries run out; r=mhenretty

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "76cfb75970783fe9f99cca63701e8d357efc03b5", 
+    "revision": "efe61b291757751c1ac1f7898d165d241e0c2113", 
     "repo_path": "/integration/gaia-central"
 }