[fix] Makefile target gh-pages & flatten history of branch gh.pages

[return42]

[fix] Makefile target gh-pages & flatten history of branch gh.pages

1. This patch fixes error:

    rm -rf gh-pages/
    make V=1 gh-pages
        make[1]: Leaving directory '/800GBPCIex4/share/searx'
    [ -d "gh-pages/.git" ] || git clone  gh-pages
    fatal: repository 'gh-pages' does not exist
   

2. The gh-page build has been moved to ./build/gh-pages this also affects
   'travis-gh-pages'

3. The gh-pages commit messages now includes a ref to the repository and commit

4. Since a gh-pages history has only the drawback that the reposetory grows
   fast, this patch also flattens the history:

    cd build/gh-pages/; git log --oneline
    bash: cd: build/gh-pages/: Datei oder Verzeichnis nicht gefunden
    026126b (HEAD -> gh-pages, origin/gh-pages) make gh-pages: from https://github.com/return42/searx.git@71d66979c2935312e0aed7fc7c3cf6199fbe88a2
   

Related issues

Remove cryptic fly dirt from the commit message: JamesIves/github-pages-deploy-action#576

[return42]

I implemented a solution ... using git worktree .. also see updated #2514 (comment)

Do you know why the py3.8 build fails? I guess it has nothing to do with this PR .. or did I missed something?

[dalf]

The worktree solution is nice.

Do you know why the py3.8 build fails? I guess it has nothing to do with this PR .. or did I missed something?

I know, it is not related to this PR.
It github action cache problem and perhaps

searx/utils/makefile.python

Line 101 in 71d6697

if ! cat $(PY_ENV)/requirements.sha256 2>/dev/null | sha256sum --check --status 2>/dev/null; then \

The gh-page build has been moved to ./build/gh-pages this also affects 'travis-gh-pages'

searx/.github/workflows/integration.yml

Line 83 in 71d6697

FOLDER: gh-pages

Should be FOLDER: build/gh-pages

[return42]

Should be FOLDER: build/gh-pages

Ah, OK I will fixed it / thanks!

[return42]

It github action cache problem and perhaps

I had a look but ...
I'm not very familiar with github actions :)

Do you know why it crashes now and how we can fix it?

[return42]

Just want to leave a link here: JamesIves/github-pages-deploy-action#576 (comment)

[dalf]

Thank you !