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

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https://hg.mozilla.org/integration/gaia-central/rev/901089fdfba5
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Revert "Merge pull request #14948 from timdream/keyboard-app-icon"

This reverts commit 67a82f88da231969efa4d22df9fb946abf2cf4df, reversing
changes made to c7a33340ca6d1225e8055951c714f5414498bb6c.