MULE-7557: Upgrade Http transport to use HttpClient v4 for improved outbound performance

Work in progress:

_ Fixing Patch test
MULE-7557: Upgrade Http transport to use HttpClient v4 for improved outbound performance

Work in progress:

_ Fixing Properties test
MULE-7557: Upgrade Http transport to use HttpClient v4 for improved outbound performance

Work in progress:

_ Updating HttpResponseToString to create the same output than previous version