Increase kernel_info_reply poll loop by one (#923)

Looks like the changes for jupyter/notebook#5908 introduced
an additional status response that pushed the actual 
kernel_info_reply out of the loop's range. 
Increasing it by one resolves the issue.

enterprise_gateway/tests/test_handlers.py

@@ -395,7 +395,7 @@ def test_kernel_comm(self):
         }))
 
         # Assert the reply comes back. Test will timeout if this hangs.
-        for _ in range(3):
+        for _ in range(4):
             msg = yield ws.read_message()
             msg = json_decode(msg)
             if(msg['msg_type'] == 'kernel_info_reply'):

requirements.yml

@@ -7,7 +7,7 @@ dependencies:
   - jinja2>=2.10
   - jupyter_client>=6.1
   - jupyter_core>=4.6.0
-  - notebook>=6.1.0,<6.1.6
+  - notebook>=6.1.0
   - paramiko>=2.1.2
   - pexpect>=4.2.0
   - pip

setup.py

@@ -53,7 +53,7 @@
         'jupyter_client>=6.1',
         'jupyter_core>=4.6.0',
         'kubernetes>=4.0.0',
-        'notebook>=6.1.0,<6.1.6',
+        'notebook>=6.1.0',
         'paramiko>=2.1.2',
         'pexpect>=4.2.0',
         'pycryptodomex>=3.9.7',