update URLs, metadata, extras in setup.cfg (#255)

Author: bollwyvl

setup.cfg

@@ -5,17 +5,25 @@ description = A set of server components for JupyterLab and JupyterLab like appl
 long_description = file: README.md
 long_description_content_type = text/markdown
 license_file = LICENSE
+project_urls =
+    Documentation = https://jupyterlab-server.readthedocs.io
+    Funding = https://numfocus.org/donate-to-jupyter
+    Source = https://github.com/jupyterlab/jupyterlab_server
+    Tracker = https://github.com/jupyterlab/jupyterlab_server/issues
 author = Jupyter Development Team
 author_email = [email protected]
-url = https://jupyter.org
+url = https://jupyterlab-server.readthedocs.io
 platforms = Linux, Mac OS X, Windows
 keywords = jupyter, jupyterlab
 classifiers =
+    Framework :: Jupyter
+    Framework :: Jupyter :: JupyterLab
     Intended Audience :: Developers
-    Intended Audience :: System Administrators
     Intended Audience :: Science/Research
+    Intended Audience :: System Administrators
     License :: OSI Approved :: BSD License
     Programming Language :: Python
+    Programming Language :: Python :: 3 :: Only
     Programming Language :: Python :: 3.7
     Programming Language :: Python :: 3.8
     Programming Language :: Python :: 3.9
@@ -32,27 +40,25 @@ install_requires =
     jinja2>=3.0.3
     json5
     jsonschema>=3.0.1
+    jupyter_server>=1.8,<2
     packaging
     requests
 
-    jupyter_server~=1.8
-
 [options.extras_require]
+openapi =
+    openapi_core>=0.14.2
+    ruamel.yaml
 test =
+    %(openapi)s
     codecov
     ipykernel
-    pytest>=5.3.2
-    pytest-cov
     jupyter_server[test]
+    openapi-spec-validator<0.5
     pytest-console-scripts
+    pytest-cov
+    pytest>=5.3.2
     strict-rfc3339
     wheel
-    openapi-spec-validator<0.5
-    openapi_core>=0.14.2
-    ruamel.yaml
-openapi =
-    openapi_core>=0.14.2
-    ruamel.yaml
 
 [options.packages.find]
 exclude =