docs: share --reload-systemd option between quadlet install and rm

[kovan]

Extract the --reload-systemd option text into a shared option file
and reference it with @@option in both manpages, following the
established pattern for shared options.

Changes:

• Create docs/source/markdown/options/reload-systemd.md with the shared option text
• Rename podman-quadlet-install.1.md to .md.in and use @@option reload-systemd
• Rename podman-quadlet-rm.1.md to .md.in and use @@option reload-systemd

Fixes #28370

[packit-as-a-service]

[NON-BLOCKING] Packit jobs failed. @containers/packit-build please check. Everyone else, feel free to ignore.

[danishprakash]

You would want to run make docs to generate the man pages from the now templated files, and then commit them.

[Honny1]

I think that podman-quadlet-install.1.md and podman-quadlet-rm.1.md must be added to .gitignore.

[kovan]

Thanks for the review. I ran hack/markdown-preprocess and the generated .md files look correct (verified in a previous comment).

Looking at the existing pattern - podman-quadlet-list.1.md.in also has a generated .md that is not tracked in git - so I believe the current state is correct: only the .md.in files and the shared option file are committed, and the generated .md files remain untracked.

Should I add them to .gitignore explicitly as @Honny1 suggests, or is the current behavior (untracked but not gitignored) consistent with how other .md.in files are handled?

[TomSweeneyRedHat]

The changes LGTM.
I'm not sure about the .gitignore need.

[Honny1]

It should be in this .gitignore file (https://github.com/containers/podman/blob/main/docs/source/markdown/.gitignore), though I didn't check the full path.