Remove useless file from tracked tree

preview/docs/_data/vars.yaml

-### BEGIN MKDOCS TEMPLATE ###
-### WARNING, DO NOT UPDATE CONTENT BETWEEN MKDOCS TEMPLATE TAG !###
-### Modified content will be overwritten when updating.###
-
-# Extra Data Information & Customization
-# ===========================================================================
-# Dictionnary storing variables to be used as "Jinja2" variables within
-# markdown files and _data/plugins.py
-
-# Mkdocs.yaml
-# ---------------------------------------------------------------------------
-# Here you can overwrite main key you could find in mkdocs.yaml
-
-# The name of your site, if not specified, will be the entry `name` of the repo in
-# `_data/repo_name.yaml`
-#site_name: "Your Site Name"
-
-# The site description of your site, if not specified will be the description
-# of the repo in `_data/repo_name.yaml`
-#site_desc: "A short description"
-
-# The url of your site, if not specified, then the site_url will be build from
-# the key `site_base_url` below and the `url_slug_with_namespace` in
-# `_data/repo_name.yaml`. If `site_base_url` is not specified, then value of
-# `site_url` will not be overwritten.
-#site_url: "https://my_site.tld"
-
-# The name or company which old the copyright. No need to specify any date
-# as it will be built based on the first commit of your repo. If not specify,
-# then no copyright will be shown on the footer of the documentation.
-#copyright: "Firstname Lastname"
-
-# Name of your repo, if not specified, will be the key `mkdocs_repo_name` in
-# `_data/repo_name.yaml` If value is EXACTLY "!!git_platform", then the value
-# will be `git_platform["name"]` (see below).
-#repo_name: "My Repo Name"
-
-# URL to the source code of your repo. If not specified, will be build from
-# `git_platform["url"]` (see below) and `repo_name["git_slug_with_namespace"]`
-# in `_data/repo_name.yaml`.
-#repo_url: "https://mygit.tld/namespace/repo_name
-
-# You can override every entry of the `theme` key in `mkdocs.yaml`, here.
-# Usefull to override templated mkdocs.
-#
-# REMARK, ONLY FOR MATERIAL-MKDOCS THEME
-#   If `theme["logo"]` is not specified, i.e. path to the logo image, then it
-#   will be set to the value of the key `repo_name["logo"]` in
-#   `_data/repo_name.yaml` if specified.
-#
-#   If `theme["favicon"]` is not specified, i.e. path to the favicon image,
-#   then it will be set to the value of the key `repo_name["logo"]` in
-#   `_data/repo_name.yaml` if specified.
-#
-#   If `theme["icon"]["repo"]` is not specified, i.e. icon "path" (see
-#   https://squidfunk.github.io/mkdocs-material/reference/icons-emojis/) that
-#   will be shown on the top rigt corner in front off the repo name, then it
-#   will be set to the value of the key `git_platform["icon"]` (see below).
-#theme:
-#  logo: "path/to/logo.svg"
-#  icon:
-#    repo:  fontawesome/brands/gitlab
-#  favicon: "path/to/favicon.svg"
-
-# Main repo configuration
-# ---------------------------------------------------------------------------
-# Here you can specify variable about your main repo documentation
-
-# The base url of your site, e.g. if you are using multiple nested
-# documentation build with monorepo, you might want to share the same base URL
-# for all your repo, then build link from the repo["url_slug_with_namespace"].
-#site_url: "https://my_site.tld"
-
-
-# Git platform
-# ---------------------------------------------------------------------------
-# In this REQUIRED section you will be able to specify some information for you
-# git platform hosting your repo. This section will be used to automatically
-# setup configuration for mkdocs such as `repo_url`, theme["icon"]["repo"] etc.
-
-# Main dict entry
-git_platform:
-  # The logo of the git platform you use. Not used in mkdocs configuration but
-  # can be used in markdown documentation file.
-  logo: " "
-  # Icon "path" (see
-  # https://squidfunk.github.io/mkdocs-material/reference/icons-emojis/) that
-  # will be shown on the top rigt corner in front off the repo name if not
-  # specified in `theme["icon"]["repo"]`.
-  icon: "fontawesome/brands/gitlab"
-  # Name of the platform you use.
-  name: "Framagit"
-  # URL of the platform you use, to be able to set `repo_url` for mkdocs
-  # configuration.
-  url: "https://framagit.org/"
-
-### END MKDOCS TEMPLATE ###