Upgrade CosmJS to 0.31 and cosmjs-types to 0.8.0

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🦋 Changeset detected

Latest commit: 5a1bcf7f987ebe6e3945c0abc56ecf5936b68517

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

| Name | Type | | --------------- | ----- | | @confio/relayer | Minor |

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