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

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https://hg.mozilla.org/integration/gaia-central/rev/6041f05d17a9
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #26703 from KevinGrandon/bug_1109920_remove_ftu_migration

Bug 1109920 - Remove collection migration code from FTU

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https://hg.mozilla.org/integration/gaia-central/rev/aab1b7ed1124
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1109920 - Remove collection migration code from FTU r=sfoster

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https://hg.mozilla.org/integration/gaia-central/rev/9227cfe6c5df
Author: Russ Nicoletti <rnicoletti@mozilla.com>
Desc: Merge pull request #26456 from russnicoletti/bug-1095826

Bug 1095826 - [RTL][Video] Thumbnail images do not appear r=djf

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https://hg.mozilla.org/integration/gaia-central/rev/a487a1ffdf26
Author: Russ Nicoletti <rnicoletti@mozilla.com>
Desc: Bug 1095826 - [RTL][Video] Thumbnail images do not appear
Bumping manifests a=b2g-bump