Update dependency @truffle/contract to v4.3.9

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
@truffle/contract	4.3.8 -> 4.3.9

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Release Notes

trufflesuite/truffle

### [`v4.3.9`](https://togithub.com/trufflesuite/truffle/compare/63841f5dad1c35863ea25a50cd3829782e7b5298...5bb77e271a6d4a6982026d5d5dda1054fa21af09) [Compare Source](https://togithub.com/trufflesuite/truffle/compare/63841f5dad1c35863ea25a50cd3829782e7b5298...5bb77e271a6d4a6982026d5d5dda1054fa21af09)

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