Changes to .gitignore affect build

[fiesh]

I suppose this isn't actually an issue of this template but rather some underlying code, but I'm uncertain. I'm thankful for feedback.

Alas, hugo writes, amonst other things, hugo_stats.json to the source directory.
Thus it should go into .gitignore.

Doing

/tmp % git clone --depth 1 --branch demo https://github.com/writeonlycode/hugo-agency-web.git agency
Cloning into 'agency'...                                                                                                                                                                                             
remote: Enumerating objects: 52, done.                                                                    
remote: Counting objects: 100% (52/52), done.                                                             
remote: Compressing objects: 100% (45/45), done.
remote: Total 52 (delta 1), reused 45 (delta 1), pack-reused 0 (from 0)                                                                                                                                              
Receiving objects: 100% (52/52), 2.47 MiB | 9.13 MiB/s, done.
Resolving deltas: 100% (1/1), done.
/tmp % cd agency
/tmp/agency (demo) % npm install
                                                     
added 55 packages, and audited 56 packages in 39s
                                                     
9 packages are looking for funding
  run `npm fund` for details
                                                     
found 0 vulnerabilities
/tmp/agency (demo) % PORT=12345
/tmp/agency (demo) % podman run -v /tmp/agency:/homepage -p $PORT:$PORT docker.io/hugomods/hugo:ci server -s /homepage -p $PORT -b some.host.name.tld -d /tmp/public --noBuildLock

works fine and serves everything correctly.

However

/tmp/agency (demo✗) % echo hugo_stats.json >> .gitignore
/tmp/agency (demo✗) % podman run -v /tmp/agency:/homepage -p $PORT:$PORT docker.io/hugomods/hugo:ci server -s /homepage -p $PORT -b some.host.name.tld -d /tmp/public --noBuildLock

produces an incorrect CSS file with fonts missing and everything rendering incorrectly. This took me a solid 2 hours to find, and I still cannot even fathom how one can make a build depend on .gitignore.