I used Astro for some projects as well, but didn't get near this complex. I just ran the Astro build locally, and pushed the resulting static site to Github pages.
I can see needing more if you've got a team contributing, but if this is for a blog, I'm not sure why you'd need even this little bit of engineering.
I have this dream that one day I can write markdown files from my phone (or buy an iPad), and with some git software I can push it to GitLab, which will trigger a deploy pipeline. But sure, pushing from your local machine works as well.
I can see needing more if you've got a team contributing, but if this is for a blog, I'm not sure why you'd need even this little bit of engineering.