Remove Travis CI config

Create Github Actions config
Split tox ini into one per supported distro so they can be run seperately

Signed-off-by: Adam Warner <me@adamwarner.co.uk>

test/conftest.py

@@ -70,15 +70,7 @@ def args(request):
 
 
 @pytest.fixture(params=[
-    'debian_9',
-    'debian_10',
-    'centos_7',
-    'centos_8',
-    'fedora_31',
-    'fedora_32',
-    'ubuntu_16',
-    'ubuntu_18',
-    'ubuntu_20'
+    'test_container'
 ])
 def tag(request):
     '''
@@ -161,4 +153,4 @@ def mock_command_2(script, args, container):
 def run_script(Pihole, script):
     result = Pihole.run(script)
     assert result.rc == 0
-    return result
+    return result