Cherrypick PR #1716 from upstream

[davecrighton]

Proposed changes

This PR cherrypicks in changes from hyperledger-firefly#1716 into the Kaleido fork of firefly-core.

From that PR:

This change tests the error string before making an update to the operations table checking that it is a valid UTF-8 string and does not contain null bytes. The second check is required because UTF-8 considers a single null byte to be a valid string but Postgres does not.

Fixes hyperledger-firefly#1717

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Types of changes

• Bug fix
• New feature added
• Documentation Update

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Other Information

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