Give Waffle runtime augment its own interface

[flux627]

• [ ] (If this PR includes a documentation change) This PR's branch was created from the website branch, and this PR uses the website branch as its base branch.
• [ ] (If this PR includes a bug fix) Relevant tests have been included.
• [ ] (If this PR includes a new feature) The change was previously discussed on an Issue or with someone from the team.
• [x] I didn't do anything of this.

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Re: NomicFoundation/hardhat-waffle#3

This change allows projects like TypeChain to augment Hardhat's Waffle integration (specifically, overloading deployContract for type support). Should have no other consequence.

[alcuadrado]

Thanks for sending this PR!

I only left a minor comment.

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[github-actions[bot]]

This PR was marked as stale because it didn't have any activity in the last 30 days. Please excuse us if we didn't have enough time to review it and get it merged. If you are still interested in getting these changes applied, please leave a comment indicating so. Otherwise, it will be closed in 7 days.

[fvictorio]

Hey @flux627, sorry for closing this, but we are moving hardhat-waffle to another repository. If you want, you could rebase this change there, although I would understand if you no longer care about this change after all this time :sweat_smile:.