Bumping gaia.json for 4 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/8fc02ff39964
Author: Arnau <arnau@arnaumarch.com>
Desc: Merge pull request #18285 from rnowm/993151

Bug 993151 - [B2G][Contacts]When editing a Facebook contact r=arcturus

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https://hg.mozilla.org/integration/gaia-central/rev/f8cf881bb861
Author: rnowm <arnau@arnaumarch.com>
Desc: Bug 993151 - [B2G][Contacts]When editing a Facebook contact, the blue highlight box does not fully cover the section that can't be edited

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https://hg.mozilla.org/integration/gaia-central/rev/ca9ea6758bf3
Author: gitmai <mri@tid.es>
Desc: Merge pull request #18197 from gitmai/bug-991831-widget-loads-slowly

Bug 991831 -[B2G][Tarako][Cost Control] The data usage bar in the notifi...
r=salva

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https://hg.mozilla.org/integration/gaia-central/rev/c6aac9f5efdb
Author: mai <mri@tid.es>
Desc: Bug 991831 -[B2G][Tarako][Cost Control] The data usage bar in the notifications pull-down menu loads in slowly

b2g/config/gaia.json

@@ -4,6 +4,6 @@
         "remote": "", 
         "branch": ""
     }, 
-    "revision": "c766bc0d49af19f18788ad8ed0542b82db81f1d8", 
+    "revision": "8fc02ff399640425b8394f3c90795a7b96755a1f", 
     "repo_path": "/integration/gaia-central"
 }