changed some latex header for fewer warnings

_config.yml

@@ -3,8 +3,8 @@ description: >-
   Vorlesungsskript für die Vorlesung "Data Science" an der HHU Düsseldorf
 author:         "Konrad Völkel"
 email:          "datascience@konradvoelkel.com"
-copyright:      "2024 CC-BY-SA 4.0"
-release:        "0.2"
+copyright:      "2025 CC-BY-SA 4.0"
+release:        "0.3"
 logo:           "images/logo-wide.svg"
 exclude_patterns: ["README.md", "LICENSE", ".git/*", ".venv/*"]
 only_build_toc_files: true
@@ -23,8 +23,8 @@ launch_buttons:
   
 html:
   use_repository_button:        true
-  use_issues_button:            true
-  #use_edit_page_button:         true
+  use_issues_button:            false
+  use_edit_page_button:         false
   use_multitoc_numbering:       true
   favicon:                      "images/favicon.ico"
   baseurl:                      "https://voelkel.pages.cs.uni-duesseldorf.de/ds-skript/"
@@ -53,7 +53,8 @@ sphinx:
     nb_execution_show_tb: True
     latex_elements:
       preamble: |+
-        \pgfplotsset{compat=1.17}
+        \pgfplotsset{compat=1.18}
+        \setdefaultlanguage{ngerman}
     language: de
     html_css_files: ["custom.css"]
     bibtex_bibfiles: