Document Docker usage (#2257)
Document Docker usage (#2257)

* Refs #12439: Modified Docker section of README.md

Signed-off-by: Javier Santiago <76c9493cb85bb3c6bfa27a77acbe38b9f95fbfad@eprosima.com>

* Refs #12439: Fixed URL errata

Signed-off-by: Javier Santiago <76c9493cb85bb3c6bfa27a77acbe38b9f95fbfad@eprosima.com>
eProsima/Fast-DDS,eProsima/Fast-DDS,eProsima/Fast-RTPS,eProsima/Fast-RTPS,eProsima/Fast-DDS,eProsima/Fast-DDS,eProsima/Fast-RTPS,eProsima/Fast-DDS,eProsima/Fast-RTPS,eProsima/Fast-RTPS