chore: update start.md (#1633)

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Fixes #1631 🦕

docs/start.md

@@ -149,5 +149,5 @@ Use the [APIs Explorer](https://developers.google.com/apis-explorer/) to browse
 
 ## Library reference documentation
 
-[Core library documentation](http://googleapis.github.io/google-api-python-client/docs/epy/index.html).
-and [Library reference documentation by API](dyn/index.md). is available.
+[Core library documentation](http://googleapis.github.io/google-api-python-client/docs/epy/index.html)
+and [Library reference documentation by API](dyn/index.md) are available.