Disable pytest capturing so unexpected writes are seen

Author: mnaberez

tox.ini

@@ -10,7 +10,7 @@ deps =
     mock >= 0.5.0
 passenv = END_TO_END
 commands =
-    pytest {posargs}
+    pytest --capture=no {posargs}
 
 [testenv:py27-configparser]
 ;see https://github.com/Supervisor/supervisor/issues/1230
@@ -24,15 +24,15 @@ commands = {[testenv]commands}
 [testenv:cover]
 basepython = python2.7
 commands =
-    pytest --cov=supervisor --cov-report=term-missing --cov-report=xml {posargs}
+    pytest --capture=no --cov=supervisor --cov-report=term-missing --cov-report=xml {posargs}
 deps =
     {[testenv]deps}
     pytest-cov
 
 [testenv:cover3]
 basepython = python3.7
 commands =
-    pytest --cov=supervisor --cov-report=term-missing --cov-report=xml {posargs}
+    pytest --capture=no --cov=supervisor --cov-report=term-missing --cov-report=xml {posargs}
 deps =
     {[testenv:cover]deps}