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

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https://hg.mozilla.org/integration/gaia-central/rev/39decead779c
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Merge pull request #23942 from jmcanterafonseca/fix_buttons_export_import

Bug 1065908 - Incorrect position of buttons in export/import options

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https://hg.mozilla.org/integration/gaia-central/rev/44ef3bed86f1
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Bug 1065908 - Incorrect position of buttons in export/import options
Bumping manifests a=b2g-bump