Remove hint to URL package

slides/references-and-footnotes.de.md

@@ -13,10 +13,6 @@ Referenzen und Fußnoten
 Fußnoten <span class="emoji">📎</span>
 
 @content
-``` {.hljs .lang-tex}
-\usepackage{hyperref}
-```
-
 Die Nummerierung erfolgt automatisch und ist fortlaufend, unabhängig davon, ob ein neuer Abschnitt beginnt.
 
 ``` {.hljs .lang-tex}

slides/references-and-footnotes.en.md

@@ -13,14 +13,8 @@ References and footnotes
 Footnotes <span class="emoji">📎</span>
 
 @content
-``` {.hljs .lang-tex}
-\usepackage{hyperref}
-```
-
 Footnotes are automatically numbered consecutively, independent of sections.
 
-(Here, `hyperref` is used for the `\url` command, it is not necessary for footnotes per se.)
-
 ``` {.hljs .lang-tex}
 The wild boar (\textit{Sus scrofa}), also 
 known as the wild swine, common wild pig,