Update Distro to Include rti-connext-dds-7.7.0

[fgallegosalido]

Include the package rti-connext-dds-7.7.0 in the rosdep/base.yaml file. This is similar to what's been done in #44821.

This update is necessary to complete the related issue ros2/rmw_connextdds#218.

@mjcarroll we will need assistance to add the new rti-connext-dds-7.7.0 Debian packages to the ROS bootstrap repository.

[mjcarroll]

@cottsay do you have everything that you need here to make this happen?

[cottsay]

We just got the Connext 7.7.0 binaries late last week. They're now available in our repositories, so this work can continue.