Correctly decode metadata.json into a utf8 str

rules_python/whl.py

diff --git a/rules_python/whl.py b/rules_python/whl.py
index 2905d77..97f9e41 100644
--- a/rules_python/whl.py
+++ b/rules_python/whl.py
@@ -58,7 +58,7 @@
     # directory.
     with zipfile.ZipFile(self.path(), 'r') as whl:
       with whl.open(os.path.join(self._dist_info(), 'metadata.json')) as f:
-        return json.loads(f.read())
+        return json.loads(f.read().decode("utf-8"))
 
   def name(self):
     return self.metadata().get('name')