Update Rust version used to build documentation [ci skip]

.readthedocs.yaml

@@ -10,7 +10,7 @@ build:
   os: ubuntu-22.04
   tools:
     python: "3.11"
-    rust: "1.64"
+    rust: "1.70"
 
 # Build documentation in the "docs/" directory with Sphinx
 sphinx: