Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-2_1/rev/675a477b8c31
Author: Guillaume Marty <edo999@gmail.com>
Desc: Follow up on Bug 1057977 - [Status Bar] Remove AM/PM indicator

Conflicts:
	build/config/common-settings.json
Bumping manifests a=b2g-bump