bring coverage test closer to py-unittest

Author: GarethCabournDavies

tox.ini

@@ -84,13 +84,10 @@ commands = bash tools/pycbc_test_suite.sh
 
 [testenv:py-coverage]
 deps =
-    {[base]deps}
+    {[testenv]deps}
     coverage
-    pytest
-conda_deps =
-    {[base]conda_deps}
 commands =
-    python -m coverage run --source=pycbc -m pytest test
+    python -m coverage run --source=pycbc -m pytest
     python -m coverage html -d htmlcov
     python -m coverage report -m
 passenv = LAL_DATA_PATH