Merge pull request #10907 from dhalbert/rstjinja-parallel-safe

fix warnings during RTD builds

Author: dhalbert

docs/rstjinja.py

@@ -38,3 +38,7 @@ def rstjinja(app, docname, source):
 
 def setup(app):
     app.connect("source-read", rstjinja)
+    return {
+        "parallel_read_safe": True,
+        "parallel_write_safe": True,
+    }