Rename master branch to main

markdown.dtx

@@ -11345,14 +11345,14 @@ conference article:
 %    \usepackage[theme=witiko/graphicx/http]{markdown}
 %    \begin{document}
 %    \begin{markdown}
-%    ![img](https://github.com/witiko/markdown/raw/master/banner.png
+%    ![img](https://github.com/witiko/markdown/raw/main/banner.png
 %           "The banner of the Markdown package")
 %    \end{markdown}
 %    \end{document}
 %    ```````
 %    Typesetting the above document produces the output shown in
 %    Figure~\ref{fig:witiko/graphicx/http}.
-%    ![img](https://github.com/witiko/markdown/raw/master/banner.png
+%    ![img](https://github.com/witiko/markdown/raw/main/banner.png
 %           "The banner of the Markdown package \label{fig:witiko/graphicx/http}")
      The theme requires the \pkg{catchfile} \LaTeX{} package and a Unix-like
      operating system with GNU Coreutils `md5sum` and either GNU Wget or cURL
@@ -11371,7 +11371,7 @@ following content:
 \usepackage[theme=witiko/graphicx/http]{markdown}
 \begin{document}
 \begin{markdown}
-![img](https://github.com/witiko/markdown/raw/master/banner.png
+![img](https://github.com/witiko/markdown/raw/main/banner.png
        "The banner of the Markdown package")
 \end{markdown}
 \end{document}
@@ -11383,7 +11383,7 @@ lualatex document.tex
 A PDF document named `document.pdf` should be produced and contain the
 following image:
 
-> ![img](https://github.com/witiko/markdown/raw/master/banner.png
+> ![img](https://github.com/witiko/markdown/raw/main/banner.png
 >        "The banner of the Markdown package")
 
 %</manual-options>