Move development dependencies from dev-requirements.txt to pyproject.toml

Author: gollux

dev-requirements.txt

@@ -56,6 +56,18 @@ dependencies = [
 Documentation = "https://cms.readthedocs.io/"
 Repository = "https://github.com/cms-dev/cms"
 
+[project.optional-dependencies]
+devel = [
+    # Only for testing
+    "beautifulsoup4>=4.8,<4.14",
+    "coverage>=4.5,<7.10",
+    "pytest",
+    "pytest-cov",
+
+    # Only for building documentation
+    "Sphinx>=1.8,<1.9",
+]
+
 [build-system]
 requires = ["setuptools < 81", "babel == 2.12.1"]
 build-backend = "setuptools.build_meta"