* fix(user_api_key_auth.py): fix passing `x-litellm-api-key` to user api key auth
Support using this when given, or bearer token when given
Fixes issue with auth on vertex passthrough
* test(test_user_api_key_auth.py): use new fastapi.security check
* fix(user_api_key_auth.py): allow key at budget, to still call non-llm api endpoints
Fixes issue where key at budget, couldn't call `/key/info`