Fix rtd yaml mistake

Author: amykyta3

.readthedocs.yaml

@@ -6,6 +6,8 @@ build:
   os: ubuntu-22.04
   tools:
     python: "3.11"
+  apt_packages:
+    - graphviz
 
 sphinx:
   configuration: docs/conf.py
@@ -15,8 +17,3 @@ python:
     - requirements: docs/requirements.txt
     - method: pip
       path: .
-
-
-build:
-  apt_packages:
-    - graphviz