pylint: fix multiple-statements cases

Fix all cases of C0321 multiple-statements.

Part of #270

Author: DifferentialOrange

test/suites/lib/tarantool_server.py

@@ -72,7 +72,8 @@ def script_dst(self):
 
     @property
     def script(self):
-        if not hasattr(self, '_script'): self._script = None
+        if not hasattr(self, '_script'):
+            self._script = None
         return self._script
 
     @script.setter