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

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https://hg.mozilla.org/integration/gaia-1_3/rev/f28431b8b326
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #18876 from azasypkin/v1.3-bug-999286-home-activity

Bug 999286 - [Sora][Message]The content is lost after do some operations. r=julien

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https://hg.mozilla.org/integration/gaia-1_3/rev/ed985c70b8a4
Author: Aleh Zasypkin <azasypkin@mozilla.com>
Desc: Bug 999286 - [Sora][Message]The content is lost after do some operations. r=julien
Bumping manifests a=b2g-bump