Trailing forward slash causes the Auth0 /userinfo route to fail

[danohn]

The server example.env currently contains a trailing forward slash for the AUTH0_ISSUER_BASE_URL:

twilio-voice-react-native-app/server/example.env

Line 37 in b568391

AUTH0_ISSUER_BASE_URL=https://xxxxxxxxx.us.auth0.com/

As a result, the getUserInfo function sends the axios request as //userinfo which causes Auth0 to return 404 Not Found:

twilio-voice-react-native-app/server/src/utils/auth.ts

Line 36 in b568391

const userInfoUrl = `${auth0Url}/userinfo`;