[Security] Bump idna from 3.6 to 3.7

Bumps [idna](https://github.com/kjd/idna) from 3.6 to 3.7. **This update includes a security fix.**
- [Release notes](https://github.com/kjd/idna/releases)
- [Changelog](https://github.com/kjd/idna/blob/master/HISTORY.rst)
- [Commits](https://github.com/kjd/idna/compare/v3.6...v3.7)

Pipfile.lock

@@ -172,6 +172,7 @@
                 "sha256:028ff3aadf0609c1fd278d8ea3089299412a7a8b9bd005dd08b9f8285bcb5cfc",
                 "sha256:82fee1fc78add43492d3a1898bfa6d8a904cc97d8427f683ed8e798d07761aa0"
             ],
+            "index": "pypi",
             "markers": "python_version >= '3.5'",
             "version": "==3.7"
         },