Reuse test data from upload.

slapos/libnetworkcachetests.py

@@ -30,11 +30,8 @@ class OnlineTest(unittest.TestCase):
     self.test_data.seek(0)
 
   def test_upload(self):
-    content = tempfile.TemporaryFile()
-    content.write('''This is content''')
-    content.seek(0)
     nc = NetworkcacheClient(self.shacache, self.shadir)
-    nc.upload(content)
+    nc.upload(self.test_data)
 
   def test_download(self):
     # prepare some test data