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

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https://hg.mozilla.org/integration/gaia-central/rev/c2bdaf49fcdc
Author: Kenzo Ohta <mu-ota@kddi-tech.com>
Desc: Bug 900413: [Messages] Should detect and link 5 digit short codes in message text. - r=gnarf

- Updated minimum digits to be detected as a phone number to 5
- Ensured that when 5 digits, the number is only 5 characters without removing separators

Closes gh-12490