fix PyPI bdist deployment

Author: mr-c

.travis.yml

@@ -19,7 +19,8 @@ deploy:
   username: __token__
   on:
     tags: true
-    distributions: sdist bdist_wheel
+    distributions: "sdist bdist_wheel"
+    skip_existing: true
     repo: common-workflow-language/cwl-utils
   password:
     secure: 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