Fixed a few failing tests, that were failing, because of the qualified_names changes

jedi/evaluate/names.py

@@ -210,7 +210,7 @@ class ImportName(AbstractNameDefinition):
                 if module_names is None:
                     return module_names
                 return module_names + (self.string_name,)
-            return self.string_name
+            return (self.string_name,)
         return ()
 
     @property

test/test_api/test_keyword.py

@@ -42,7 +42,7 @@ def test_keyword_attributes(Script):
     assert def_.docstring()
     assert def_.description == 'keyword def'
     assert def_.get_line_code() == ''
-    assert def_.full_name == 'def'
+    assert def_.full_name is None
     assert def_.line is def_.column is None
     assert def_.in_builtin_module() is True
     assert def_.module_name in ('builtins', '__builtin__')

test/test_evaluate/test_compiled.py

@@ -169,4 +169,4 @@ def test_qualified_names(same_process_evaluator, obj, expected_names):
         same_process_evaluator,
         DirectObjectAccess(same_process_evaluator, obj)
     )
-    assert o.get_qualified_names() == expected_names
+    assert o.get_qualified_names() == tuple(expected_names)