Add pyyaml requirement

Author: tdgroot

requirements/base.txt

@@ -1,3 +1,4 @@
+# docs/ requirements
 sphinx==5.3.0
 sphinx_rtd_theme==1.1.1
 myst-parser==0.18.1
@@ -7,6 +8,8 @@ mdformat==0.7.16
 mdformat-myst==0.1.5
 mdformat-frontmatter==0.4.1
 
+# hypernode/ requirements
 beautifulsoup4==4.11.1
 markdownify==0.11.2
 python-slugify==6.1.2
+pyyaml==6.0