URL Template keys with hyphens fail

[ChrisLane]

When using a URL Template key that contains a - character, requests will fail with the following error shown on the RESTED Client page:

An error occurred while fetching the resource: TypeError: NetworkError when attempting to fetch resource.

and no error in console.

Example Data: Key: local-tests-url Value: http://localhost:7000 URL: {{local-tests-url}}/tests/authentication

Version Details: OS: macOS Catalina 10.15.3 Browser: Firefox 72.0.2 Rested Client: 2.3.1