Enhance contribution setup docs with streamlined commands

[Victor-Boyd]

As an individual contributor to this open-source project, I noticed an opportunity to enhance the contributor experience by simplifying the initial setup instructions within our documentation. This commit aims to lower the entry barrier for new contributors by providing a concise, all-in-one command sequence that facilitates the setup process.

Key Updates:

• Introduced a command for cloning the repository, ensuring newcomers start off on the right foot without having to navigate through multiple setup steps.
• Integrated the PATH environment variable update (~/.local/bin) within the setup commands to eliminate the need for manual configuration, making the environment preparation seamless.
• Combined cloning, environment setup, and dependencies installation into a singular command. This change is designed to make the first-time setup as straightforward as possible, aligning with our project's goal of being accessible and welcoming to new contributors.

Rationale:
The motivation behind these changes is to simplify the contribution process, making it more appealing and less daunting for individuals looking to contribute to our project. By streamlining the setup instructions, we hope to encourage a broader range of contributions and foster a more inclusive community.

[Ryanf55]

If you want to contribute, you should fork, then clone your fork. To be able to push, you need to use ssh cloning.

[fujitatomoya]

I am not sure if we want to introduce how to create pull request here? in general https://docs.ros.org/en/rolling/The-ROS2-Project/Contributing/Developer-Guide.html#change-control-process looks good enough for me? besides, that is the common process for any ROS 2 repositories.

here i believe that adding explanation where requirements.txt is located is better for user document. i think using mainline would be just fine as example build process here.

[Ryanf55]

Agree, I don't think every open source repository needs to explain how to use Github and forks to contribute code.

[fujitatomoya]

@Victor-Boyd thank you for the PR, i have a couple of comments.

[fujitatomoya]

I am not sure if we want to introduce how to create pull request here? in general https://docs.ros.org/en/rolling/The-ROS2-Project/Contributing/Developer-Guide.html#change-control-process looks good enough for me? besides, that is the common process for any ROS 2 repositories.

here i believe that adding explanation where requirements.txt is located is better for user document. i think using mainline would be just fine as example build process here.

[fujitatomoya]

if we want to add export, other platform command lines should be updated accordingly?

Suggested change

	export PATH="~/.local/bin:$PATH" && pip3 install --user --upgrade -r requirements.txt
	export PATH="~/.local/bin:$PATH" && pip3 install --user --upgrade -r requirements.txt

[Ryanf55]

On Ubuntu 22, it's already part of ~/.profile.
cat ~/.profile

# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/.local/bin" ] ; then
    PATH="$HOME/.local/bin:$PATH"
fi

https://askubuntu.com/questions/1144231/home-local-bin-not-in-path-for-ubuntu-19-04

Here's a dockerfile to demonstrate:

FROM ubuntu:22.04
ARG DOCKER_USER=ryan
#RUN useradd -ms /bin/bash ${DOCKER_USER} -g root -G sudo

RUN apt-get update && apt-get install sudo
RUN adduser --disabled-password --gecos '' ${DOCKER_USER}
USER ${DOCKER_USER}
WORKDIR /home/${DOCKER_USER}
CMD ["whoami"]

docker build . -t docs
docker run -w /home/ryan --net host -it docs bash
cat ~/.profile

[clalancette]

For what it is worth, I don't think it is a good idea for us to be suggesting people use export PATH=~/.local/bin:$PATH. That will almost inevitably lead to people filing bugs because we "broke" their system, and also will not work on Windows. Instead I'd much rather we say something like Use /path/to/sphinx, where sphinx might be in ~/.local/bin.