remove https from url in getAccessToken

[JVersee]

Description

BASE_URL const already includes https:// in https://live.getsilverfin.com'. In the config we have to usehttps://in that case as well and ensure no duplicatehttps://` is being used when string interpolating.

Fixes # (link to the corresponding issue if applicable)

Type of change

• [x ] Bug fix
• [ ] New feature
• [ ] Breaking change

Checklist

• [ ] README updated (if needed)
• [ ] Version updated (if needed)
• [ ] Documentation updated (if needed)