[texdoc] `texdoc yathesis`: to be cleaned up

[Denis Bitouzé]

Hi,

the output of `texdoc -l yathesis` is:

  ┌────
  │  1 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/documentation/yathesis-fr.pdf
  │    = [fr] Package documentation
  │  2 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/english/README-TRANSLATION.md
  │  3 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/code/yathesis-code.pdf
  │  4 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/documentation/logoulcofondblanc.pdf
  │  5 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/exemples/specimen/a-plat/comue.pdf
  │  6 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/exemples/specimen/a-plat/labo.pdf
  │  7 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/exemples/specimen/a-plat/paris13.pdf
  │  8 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/exemples/specimen/a-plat/these.pdf
  │  9 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/exemples/specimen/a-plat/tiger.pdf
  │ 10 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/exemples/specimen/a-plat/ulco.pdf
  │ 11 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/CHANGELOG.md
  │ 12 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/README.md
  │    = Readme
  │ 13 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/documentation/latexmkrc
  │ 14 /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/exemples/specimen/a-plat/latexmkrc
  └────

IMO, it should be (only):

  ┌────
  │  1. /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/documentation/yathesis-fr.pdf
  │   . = [fr] Package documentation
  │  2. /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/README.md
  │   . = Readme
  │  3. /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/CHANGELOG.md
  │  4. /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/english/README-TRANSLATION.md
  │  5. /home/bitouze/texlive/2022/texmf-dist/doc/latex/yathesis/french/code/yathesis-code.pdf
  └────

Thanks in advance.

Best,
-- 
Denis