Added preview functionality to the podman repo

[antedotee]

Concisely describe the change

I have added the preview functionality in this repo. Now, if anyone makes any changes to the docs, a preview link will automatically be appended to the PR description with the associated changes contributor has made to the PR. It will help other people, and specifically, maintainers, to preview the changes directly, without having to run them locally.

Below is an example of how it looks when I tried to make a change and raise a PR:

Here is the deployed link url -> https://antedotee.github.io/podman.io/pr-preview/pr-2/
I have changed the title in the hero section to see if it works, and it worked.
Here is the PR in case you want to look at it -> antedotee#2
Here is the PR description, after running the workflow to generate preview, automatically a preview link gets added to the PR description:

In case you think the changes are goof enough to merge, you will have to edit some additional settings in the repository in order to make it work.
In case workflow permissions are not already set to read and write, do it:

Additionally, you will have to go to pages section in settings and set the branch to gh-pages:

After the following, for each PR, the preview link will be in the form of https://podman.io/https:/podman.io/pr-preview/pr-/

Fixes #552

Checklist

Ensure you have completed the following checklist for your pull request to be reviewed:

• Certify you wrote the patch or otherwise have the right to pass it on as an open-source patch by signing all
  commits. (git commit -s). (If needed, use git commit -s --amend). The author email must match
  the sign-off email address. See CONTRIBUTING.md
  for more information.
• Referenced issues using Fixes: #00000 in commit message (if applicable)
• PR description, commit message, and GitHub comments are human-written, per LLM Policy

[antedotee]

In case of any doubts or clarifications needed, please let me know.