Add syntax support for Scalatest "GivenWhenThen"#282

AdamJKing wants to merge 1 commit intotypelevel:series/1.xtypelevel/cats-effect-testing:series/1.xfrom

AdamJKing:given-when-then-syntaxAdamJKing/cats-effect-testing:given-when-then-syntaxCopy head branch name to clipboard