Add testing utilities to smithy-http#588

alexgromero wants to merge 2 commits intosmithy-lang:functional-testing-frameworksmithy-lang/smithy-python:functional-testing-frameworkfrom

alexgromero:add-testing-utilities-to-smithy-httpalexgromero/smithy-python:add-testing-utilities-to-smithy-httpCopy head branch name to clipboard