Fix an inaccuracy in the SuggestStore::fetch_geonames() doc string

[0c0w3]

Pull Request checklist

• Breaking changes: This PR follows our breaking change policy
  • This PR follows the breaking change policy:
    • This PR has no breaking API changes, or
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Branch builds: add [firefox-android: branch-name] to the PR title.

[linabutler]

Stamp!

[0c0w3]

Thanks!