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

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https://hg.mozilla.org/integration/gaia-central/rev/1b5ceb13f47b
Author: Guillaume C. Marty <gmarty@users.noreply.github.com>
Desc: Merge pull request #26631 from gmarty/Bug-1107727-Better-support-data-uri-HTML-pages-browser

Bug 1107727 - Better support of data-uri HTML pages in the browser

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https://hg.mozilla.org/integration/gaia-central/rev/76a514e2da82
Author: Guillaume Marty <edo999@gmail.com>
Desc: Bug 1107727 - Better support of data-uri HTML pages in the browser
Bumping manifests a=b2g-bump