test.py: make compatible with python-3.8

* time.clock() was removed from Python 3.8 in
  python/cpython#13270

Signed-off-by: Martin Jansa <martin.jansa@lge.com>

test.py

@@ -1,7 +1,7 @@
-#!/usr/bin/env python2.6
+#!/usr/bin/env python3
 
 import sys
-from time import clock
+from time import perf_counter
 
 from p2t import *
 
@@ -50,7 +50,7 @@ def main(file_name, translate, zoom):
         polyline.append(Point(p[0],p[1]))
 
     # initialize clock
-    t0 = clock()
+    t0 = perf_counter()
 
     ##
     ## Step 1: Initialize
@@ -87,7 +87,7 @@ def main(file_name, translate, zoom):
     ##
     triangles = cdt.triangulate()
 
-    print ("Elapsed time (ms) = " + str(clock()*1000.0))
+    print ("Elapsed time (ms) = " + str(perf_counter()*1000.0))
 
     # The Main Event Loop
     done = False