Revert "Update _config.yml"

This reverts commit db8f06378f.

book/_config.yml

@@ -6,6 +6,9 @@ copyright: Delft University of Technology, CC BY 4.0 # overriden by extra footer
 execute:
   execute_notebooks: "off"
 
+launch_buttons:
+  thebe: true
+
 only_build_toc_files: true
 
 html:
@@ -20,8 +23,6 @@ sphinx:
     thebe_config:
       use_thebe_lite: true
       exclude_patterns: ["**/_*.yml", "**/*.md", "**/*.ipynb"]
-    launch_buttons:
-      thebe: true
   extra_extensions:
     - sphinx.ext.imgconverter
     - download_link_replacer