chore(deps): update dependency sphinx-rtd-theme to v3

Author: renovate[bot]

pyproject.toml

@@ -50,7 +50,7 @@ optional = true
 [tool.poetry.group.docs.dependencies]
 sphinx = "^4.4"
 sphinx-issues = "^4.0.0"
-sphinx-rtd-theme = "^1.0"
+sphinx-rtd-theme = "^3.0.0"
 
 [tool.poetry.dev-dependencies]
 pytest = "*"