Update furo; simplify conf.py

Change-Id: I8f098441051dc92378dfc9ce57287c0b8e2bd621
diff --git a/requirements.txt b/requirements.txt
index 4bc87db..3b2379e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,2 @@
-furo == 2022.6.4.1
+furo == 2022.9.15
 sphinx ~= 5.0