When runUnitTest is called from erp5 testnode environt can miss PATH. Try to...

When runUnitTest is called from erp5 testnode environt can miss PATH. Try to be more defensive in this case.

slapos/recipe/erp5_test/test.py

@@ -53,7 +53,7 @@ def runUnitTest(args):
   d = args[0]
   env['OPENSSL_BINARY'] = d['openssl_binary']
   env['TEST_CA_PATH'] = d['test_ca_path']
-  env['PATH'] = ':'.join([d['prepend_path']] + os.environ['PATH'].split(':'))
+  env['PATH'] = ':'.join([d['prepend_path']] + os.environ.get('PATH', '').split(':'))
   env['INSTANCE_HOME'] = d['instance_home']
   env['REAL_INSTANCE_HOME'] = d['instance_home']
   # Deal with Shebang size limitation