requirements: docs: restrict sphinx <7 (#100)

Fixes docs build error in python 3.8+: ``` Theme error: An error happened in rendering the page Condition. Reason: UndefinedError("'style' is undefined") make: *** [Makefile:20: html] Error 2 ```
kmantel · Oct 26, 2023 · 3bc2e74 · 3bc2e74
1 parent 323a460
commit 3bc2e74
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/docs_requirements.txt b/docs_requirements.txt
@@ -1,4 +1,4 @@
 m2r2
-sphinx
+sphinx <7
 sphinx-autodoc-typehints
 sphinx-rtd-theme