Simplify test implementation

system/t07_serve/__init__.py

@@ -23,29 +23,9 @@ class RootDirInaccessible(BaseTest):
     configOverride = {
         "rootDir": "/root" # any directory that exists but is not writable
     }
+
     runCmd = "aptly serve -listen=127.0.0.1:8765"
-
-    def run(self):
-        try:
-            proc = subprocess.Popen(shlex.split(self.runCmd), stderr=subprocess.STDOUT, stdout=subprocess.PIPE, bufsize=0)
-            time.sleep(1)
-
-            conn = httplib.HTTPConnection("127.0.0.1", 8765)
-            conn.request("GET", "/")
-            r = conn.getresponse()
-            self.http_response = r.read()
-            output = os.read(proc.stdout.fileno(), 8192)
-
-        except socket_error as serr:
-            if serr.errno != errno.ECONNREFUSED:
-                raise serr
-
-        finally:
-            self.output, err = proc.communicate()
-
-    def check(self):
-        self.check_output()
-
+    expectedCode = 1
 
 class Serve1Test(BaseTest):
     """