fix: fix encoding of xml

Author: pleshevskiy

genrss/__init__.py

@@ -239,6 +239,6 @@ def xml(self, pretty: bool = False) -> str:
         """
         root = self.to_element()
 
-        return '<?xml version="1.0" encoding="UTF-8"?>\n' \
-               + ('\n' if pretty else '') \
-               + tostring(root, pretty_print=pretty).decode('utf-8')
+        return tostring(root, pretty_print=pretty, xml_declaration=True,
+                        encoding='UTF-8').\
+            decode('utf-8')

tests/test_rss.py

@@ -40,7 +40,7 @@ def test_feed_description(description, expose):
 
 
 @pytest.mark.parametrize('copyright, expose', [
-    pytest.param('copyright © genrss', 'copyright © genrss', id='copy'),
+    pytest.param('copyright © genrss', 'copyright © genrss', id='copy'),
 ])
 def test_feed_copyright(copyright, expose):
     feed = create_rss(copyright=copyright)