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

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https://hg.mozilla.org/integration/gaia-central/rev/bf844ea59173
Author: Albert <acperez@tid.es>
Desc: Merge pull request #13920 from acperez/bug-941755

Bug 941755 - Fix wrong format of singlevariant.json r=yurenju

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https://hg.mozilla.org/integration/gaia-central/rev/fe57b1415619
Author: Albert <acperez@tid.es>
Desc: Bug 941755 - Fix wrong format of singlevariant.json r=yurenju

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "bf3a67026235f2556ba2bdf2a1f4a7ac22507db6", 
+    "revision": "bf844ea59173d2f06dc6c824fe224e2e0a30f626", 
     "repo_path": "/integration/gaia-central"
 }