Fix auth redirection link

[pkukielka]

Changes

Before my change redirection URL looked like this:

https://sourcegraph.com/user/settings/tokens/new/callback?requestFrom=CODY_JETBRAINS&tokenReceiverUrl=http%3A%2F%2F127.0.0.1%3A60270%AUTH_TOKEN.auth/openidconnect/login?prompt_auth=github&pc=sams&redirect=/user/settings/tokens/new/callback?requestFrom=CODY_JETBRAINS&tokenReceiverUrl=http%3A%2F%2F127.0.0.1%3A60270%AUTH_TOKEN

Instead of:

https://sourcegraph.com/.auth/openidconnect/login?prompt_auth=github&pc=sams&redirect=/user/settings/tokens/new/callback?requestFrom=JETBRAINS&tokenReceiverUrl=http%3A%2F%2F127.0.0.1%3A59623%AUTH_TOKEN

Test plan

1. Open JetBrains with authentication capability enabled and try to login using one of the providers like GitHub
2. You should be redirected to page asking for token creation authorisation like this, NOT token token page.