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

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https://hg.mozilla.org/integration/gaia-central/rev/73d6c95cb3c9
Author: Aleh Zasypkin <aleh.zasypkin@gmail.com>
Desc: Merge pull request #20376 from azasypkin/bug-1012663-csp-compliance

Bug 1025552 - [Messages][Refactoring] Refactor attachment.js and specifically move rendering part to a separate module. r=julienw, schung

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https://hg.mozilla.org/integration/gaia-central/rev/97fbfd18d60e
Author: Aleh Zasypkin <azasypkin@mozilla.com>
Desc: Bug 1025552 - [Messages][Refactoring] Refactor attachment.js and specifically move rendering part to a separate module. r=julienw, schung
Bumping manifests a=b2g-bump