tests: make tests less make dependent

Implement command line argument parsing instead of passing arguments via
environment variables. Add script for running tests without having to
invoke make. Deprecate running tests via make.

Type: improvement
Change-Id: I2e3054a61a2ae25d460e9be00be7d7705fbf943e
Signed-off-by: Klement Sekera <ksekera@cisco.com>
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>
diff --git a/test/test_ikev2.py b/test/test_ikev2.py
index 438a674..58a7ec3 100644
--- a/test/test_ikev2.py
+++ b/test/test_ikev2.py
@@ -13,6 +13,7 @@
 )
 from ipaddress import IPv4Address, IPv6Address, ip_address
 import unittest
+from config import config
 from scapy.layers.ipsec import ESP
 from scapy.layers.inet import IP, UDP, Ether
 from scapy.layers.inet6 import IPv6
@@ -1380,7 +1381,7 @@
 
         if 'auth' in params and params['auth'] == 'rsa-sig':
             auth_method = 'rsa-sig'
-            work_dir = os.getenv('BR') + '/../src/plugins/ikev2/test/certs/'
+            work_dir = f"{config.vpp_ws_dir}/src/plugins/ikev2/test/certs/"
             self.vapi.ikev2_set_local_key(
                     key_file=work_dir + params['server-key'])