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

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https://hg.mozilla.org/integration/gaia-central/rev/118497e9bd32
Author: ochameau <poirot.alex@gmail.com>
Desc: Merge pull request #11890 from ochameau/appterminated-manifestURL

Bug 911802 - Send manifestURL on appterminated event r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/840f698275c3
Author: Alexandre Poirot <poirot.alex@gmail.com>
Desc: Bug 911802 - Send manifestURL on appterminated event

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "879ca374b3caf27e760a3209a743a4fb9ad624d0", 
+    "revision": "118497e9bd320d65b847be7b7e70c021d4ae56f4", 
     "repo_path": "/integration/gaia-central"
 }