MULE-8124: Adding body to listener not found response, functional test case for missing listener scenario and unit test case for missing path scenario.
(cherry picked from commit 793a3213a0726e88da4b26f2aff5ec2e8f41ef73)
MULE-8124: Adding matcher for HTTP response status code validation and  other changes asked for in PR.
(cherry picked from commit 7b58f646ea306725e30f2f2b8ed86052c0715383)