switch cov config to pyproject

Author: adrn

tox.ini

@@ -50,15 +50,14 @@ deps =
     devdeps: :NIGHTLY:numpy
     devdeps: git+https://github.com/astropy/astropy.git#egg=astropy
 
-# The following indicates which extras_require from setup.cfg will be installed
 extras =
     test
     extradeps: extra
 
 commands =
     pip freeze
     !cov: pytest -v --pyargs gala {toxinidir}/docs {posargs}
-    cov: pytest --pyargs gala {toxinidir}/docs --cov gala --cov-config={toxinidir}/setup.cfg {posargs} --cov-report=xml:{toxinidir}/coverage.xml --durations=16
+    cov: pytest --pyargs gala {toxinidir}/docs --cov gala --cov-config={toxinidir}/pyproject.toml {posargs} --cov-report=xml:{toxinidir}/coverage.xml --durations=16
 
 # Runs pip install -e . instead of building an sdist and installing
 usedevelop = False