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

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https://hg.mozilla.org/integration/gaia-central/rev/b952ee872198
Author: John Hu <johu@mozilla.com>
Desc: Merge pull request #19746 from huchengtw-moz/stingray-bug-1007079

Bug 1007079 - [Stingray] enable all tests of homescreen-stingray when bu..., r=lchang

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https://hg.mozilla.org/integration/gaia-central/rev/11e4d4d00b3b
Author: John Hu <johu@mozilla.com>
Desc: Bug 1007079 - [Stingray] enable all tests of homescreen-stingray when bug 1006357 is fixed
Bumping manifests a=b2g-bump