Fix build

.readthedocs.yaml

@@ -1,11 +1,8 @@
-# .readthedocs.yaml
 # Read the Docs configuration file
 # See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
 
-# Required
 version: 2
 
-# Set the OS, Python version and other tools you might need
 build:
   os: ubuntu-22.04
   tools:
@@ -15,16 +12,14 @@ build:
     # rust: "1.64"
     # golang: "1.19"
 
-# Build documentation in the "docs/" directory with mkdocs
 mkdocs:
   configuration: mkdocs.yml
 
 formats:
-  - all
+  - epub
+  - pdf
+  - htmlzip
 
-# Optional but recommended, declare the Python requirements required
-# to build your documentation
-# See https://docs.readthedocs.io/en/stable/guides/reproducible-builds.html
 python:
   install:
     - requirements: docs/requirements.txt