tests: fix worker thread initialization

from threading.thread __init__:

    This constructor should always be called with keyword arguments.

    If a subclass overrides the constructor, it must make sure to invoke
    the base class constructor (Thread.__init__()) before doing anything
    else to the thread.

Type: test
Change-Id: Ifa89202e97053a4baf19e9a0ca0913430d5087a3
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>
diff --git a/src/plugins/quic/test/test_quic.py b/src/plugins/quic/test/test_quic.py
index 152fa5e..4534c8e 100644
--- a/src/plugins/quic/test/test_quic.py
+++ b/src/plugins/quic/test/test_quic.py
@@ -14,14 +14,17 @@
     """ QUIC Test Application Worker """
     process = None
 
-    def __init__(self, build_dir, appname, args, logger, role, testcase,
-                 env={}):
+    def __init__(self, build_dir, appname, executable_args, logger, role,
+                 testcase, env=None, *args, **kwargs):
+        if env is None:
+            env = {}
         app = "%s/vpp/bin/%s" % (build_dir, appname)
-        self.args = [app] + args
+        self.args = [app] + executable_args
         self.role = role
         self.wait_for_gdb = 'wait-for-gdb'
         self.testcase = testcase
-        super(QUICAppWorker, self).__init__(self.args, logger, env)
+        super(QUICAppWorker, self).__init__(self.args, logger, env,
+                                            *args, **kwargs)
 
     def run(self):
         super(QUICAppWorker, self).run()
diff --git a/src/vcl/test/test_vcl.py b/src/vcl/test/test_vcl.py
index 804e745..d7a44ed 100644
--- a/src/vcl/test/test_vcl.py
+++ b/src/vcl/test/test_vcl.py
@@ -26,7 +26,11 @@
 class VCLAppWorker(Worker):
     """ VCL Test Application Worker """
 
-    def __init__(self, build_dir, appname, args, logger, env={}):
+    def __init__(self, build_dir, appname, executable_args, logger, env=None,
+                 *args, **kwargs):
+
+        if env is None:
+            env = {}
         vcl_lib_dir = "%s/vpp/lib" % build_dir
         if "iperf" in appname:
             app = appname
@@ -38,8 +42,9 @@
                         "%s/libvcl_ldpreload.so" % vcl_lib_dir})
         else:
             app = "%s/vpp/bin/%s" % (build_dir, appname)
-        self.args = [app] + args
-        super(VCLAppWorker, self).__init__(self.args, logger, env)
+        self.args = [app] + executable_args
+        super(VCLAppWorker, self).__init__(self.args, logger, env,
+                                           *args, **kwargs)
 
 
 class VCLTestCase(VppTestCase):