fix: Upgrade Sphinx to support Python 3.13

- Upgrade Sphinx from ^1.3.0 to ^5.0.0 to resolve 'No module named pipes' error
- Python 3.13 removed the pipes module that old Sphinx versions depend on
- Verified documentation builds successfully with Sphinx 5.3.0

Co-Authored-By: mkeeler@launchdarkly.com <keelerm84@gmail.com>

Author: devin-ai-integration[bot]

pyproject.toml

@@ -50,7 +50,7 @@ Flask = "2.2.5"
 optional = true
 
 [tool.poetry.group.docs.dependencies]
-sphinx = "^1.3.0"
+sphinx = "^5.0.0"
 sphinx-autodoc-typehints = "^1.3.0"
 sphinx-rtd-theme = "^1.3.0"
 backoff = ">=1.4.3"