[CI][Fix] Change the python version in .readthedocs.yml to solve the error: "Building wheel for cvxopt (pyproject.toml) did not run successfully."

Author: jajupmochi

.readthedocs.yml

@@ -8,7 +8,7 @@ version: 2
 build:
   os: ubuntu-22.04
   tools:
-    python: "3.12"
+    python: "3.8"
     # You can also specify other tool versions:
     # nodejs: "20"
     # rust: "1.70"