Update font awesome version

Author: stefmolin

slides/templates/larger_font/index.html.j2

@@ -127,7 +127,7 @@
 <link rel="stylesheet" href="{{ reveal_url_prefix }}/dist/theme/{{reveal_theme}}.css" id="theme">
 <!-- Font Awesome icons -->
 <link
-  href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.1.1/css/all.min.css"
+  href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.7.2/css/all.min.css"
   rel="stylesheet" type="text/css">
 
 <!-- If the query includes 'print-pdf', include the PDF print sheet -->

slides/templates/regular/index.html.j2

@@ -126,7 +126,7 @@
 <link rel="stylesheet" href="{{ reveal_url_prefix }}/dist/theme/{{reveal_theme}}.css" id="theme">
 <!-- Font Awesome icons -->
 <link
-  href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.1.1/css/all.min.css"
+  href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.7.2/css/all.min.css"
   rel="stylesheet" type="text/css">
 
 <!-- If the query includes 'print-pdf', include the PDF print sheet -->