Update dependency @types/chai to v4.3.0

Editor assessment

The subject names @types/chai and the destination version v4.3.0, which fully determines the change at a glance. The chore type and deps scope are accurate for type-definition maintenance, and no body is required because a routine version bump carries no motivation beyond dependency upkeep. No footers are present, so there is nothing malformed and nothing noisy to evaluate. Style hygiene is good: imperative phrasing, no trailing period, no ticket junk, sensible subject length, consistent language. The message is narrow but honest and complete, communicating everything a reader needs without the diff, which is the standard a maintenance commit must meet.