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

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https://hg.mozilla.org/integration/gaia-central/rev/8c2bde60533a
Author: Guillaume C. Marty <gmarty@users.noreply.github.com>
Desc: Merge pull request #26610 from gmarty/Bug-1101113-system-dialog-rtl

Bug 1101113 - (system-dialog-rtl) [META] [RTL] System Dialogs

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https://hg.mozilla.org/integration/gaia-central/rev/1c16bab9e5f8
Author: Guillaume Marty <edo999@gmail.com>
Desc: Bug 1101113 - (system-dialog-rtl) [META] [RTL] System Dialogs
Bumping manifests a=b2g-bump