Fix installation for rolling

[Ryanf55]

Purpose

• Use the correct branch
• Don't pull in vcs sources for geometry2
• Handle slam_toolbox circular dependency in the background automatically
• Add note that binaries are not available for rolling. If this changes, then a new section can be added
• Be able to compile NAV2 on rolling following the instructions verbatim without errors

How to test

Use this dockerfile:

ARG ROS_DISTRO=rolling
FROM ros:${ROS_DISTRO}-ros-core

RUN apt-get update \
    && apt-get install -y \
        ros-dev-tools \
        wget

WORKDIR /root/ros2_ws 
RUN mkdir -p ~/ros2_ws/src
RUN git clone https://github.com/ros-planning/navigation2.git --branch main ./src/navigation2
RUN rosdep init

SHELL ["/bin/bash", "-c"]
RUN apt-get update \
    && rosdep update \
    && source /opt/ros/${ROS_DISTRO}/setup.bash \
    && rosdep install -y -r --ignore-src --from-paths src

RUN source /opt/ros/${ROS_DISTRO}/setup.bash \ 
    && colcon build --symlink-install

ANd run docker build .

Note - because it's rolling, this may not be reproducible, but it works today.