feat: making ros2 installation optional in environment setup

[Owen-Liuyuxuan]

Description

Making ROS2 installation in the environment setup optional.

Expected use case:

1. Some users have installed or even lock a certain ROS2 version in their local environment before using Autoware. Giving them an option to skip the ROS2 installation makes environment setup easier for all side.
2. Exposing an argument to skip ROS2 installation for certain docker image building.

Tests performed

Not applicable.

Effects on system behavior

Not applicable.

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[Owen-Liuyuxuan]

#4585 This PR is completing the task we would like to achieve here.

[mitsudome-r]

@Owen-Liuyuxuan Is this a duplicate work of #4585?

[Owen-Liuyuxuan]

Our final target is the same though. So it is OK to close it now.