update project urls

Author: drbenvincent

pyproject.toml

@@ -85,7 +85,10 @@ test = ["pytest", "pytest-cov", "codespell", "nbformat", "nbconvert"]
 [project.urls]
 Homepage = "https://github.com/pymc-labs/CausalPy"
 "Bug Reports" = "https://github.com/pymc-labs/CausalPy/issues"
-"Source" = "https://github.com/pymc-labs/CausalPy"
+Source = "https://github.com/pymc-labs/CausalPy"
+Documentation = "https://causalpy.readthedocs.io"
+Changelog = "https://github.com/pymc-labs/CausalPy/releases"
+Discussions = "https://github.com/pymc-labs/CausalPy/discussions"
 
 [tool.pytest.ini_options]
 addopts = [