Small fix in the config.tomltrust_threshold for chain ibc-1

[ljoss17]

Closes: #XXX

Description

The trust_threshold default has been changed to 2/3 #2876.
This PR updates the trust_threshold in the config.toml for chain ibc-1 to match the default value.

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PR author checklist:

• Added changelog entry, using unclog.
• Added tests: integration (for Hermes) or unit/mock tests (for modules).
• Linked to GitHub issue.
• Updated code comments and documentation (e.g., docs/).
• Tagged one reviewer who will be the one responsible for shepherding this PR.

Reviewer checklist:

• Reviewed Files changed in the GitHub PR explorer.
• Manually tested (in case integration/unit/mock tests are absent).