chore(deps): update dependency sphinx to v8

Author: renovate[bot]

pyproject.toml

@@ -48,7 +48,7 @@ defusedxml = "^0.7.1"
 optional = true
 
 [tool.poetry.group.docs.dependencies]
-sphinx = "^4.4"
+sphinx = "^8.0.0"
 sphinx-issues = "^4.0.0"
 sphinx-rtd-theme = "^1.0"