feat: add build url on pact publish

[konalegi]

Add buildUrl parameter for the pact publication function. Follow-up for #352

[TimothyJones]

Thanks for this!

Two small issues:

1. The commit message here will appear in the release notes - However, this message currently isn't suitable for the release notes as it's a bit cryptic. (see our instructions here: https://github.com/pact-foundation/pact-js-core/blob/master/CONTRIBUTING.md#release-notes for guidelines).

Could you choose one of:

• Force push (or otherwise resubmit) with a release-notes appropriate message (if you're not sure what to put, I think something like "feat: Add buildUrl option to Verifier API")
• Let us squash merge it with a new message (if we do this, you don't get appropriately marked as a contributor, I think)

2. Could you add the new option to the documentation in the readme please?

[TimothyJones]

Also, it's currently failing the prettier format check step. You can fix this with npm run format:fix and committing the result.

[konalegi]

@TimothyJones thanks for your review.

• Added documentation
• Fixed prettier
• Updated commit message but feel free to update it before merging.

Thanks!

[TimothyJones]

Thanks very much! I'll release this now

[TimothyJones]

This is now released in pact-core@13.4.0 and pact-node@10.16.0

Thanks again for the PR! Welcome to the list of pact-js contributors :)