updating ebook script

Author: jayair

etc/ebook/build-pdf.rb

@@ -82,7 +82,9 @@ def build_chapter chapter_data
 
     chapter.force_encoding(::Encoding::UTF_8)
 
-    chapter_front_matter = YAML.load_file("../../_chapters/#{chapter_name}.md")
+    # Update for Ruby 3.2
+    # chapter_front_matter = YAML.load_file("../../_chapters/#{chapter_name}.md")
+    chapter_front_matter = YAML.safe_load_file("../../_chapters/#{chapter_name}.md", permitted_classes: [Time])
 
     #################
     # Validations