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

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https://hg.mozilla.org/integration/gaia-central/rev/6b3922b505b1
Author: Borja Salguero <borjasalguero@users.noreply.github.com>
Desc: Merge pull request #11897 from gasolin/issue-911684

Bug 911684 - [FTU] hide SIM contact import when not support telephony r=borjasalguero

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https://hg.mozilla.org/integration/gaia-central/rev/4a6100bd2ea8
Author: gasolin <gasolin@gmail.com>
Desc: Bug 911684 - [FTU] hide SIM contact import when not support telephony