Config setting studio.url is not respected

[georgegeddes]

Bug Report

Description

The studio.url config setting is ignored by dvc, and the login link is always to studio.iterative.ai.

Reproduce

$ dvc init
$ dvc config studio.url https://example.com
$ dvc config studio.url
https://example.com
$ dvc studio login
Opening link for login at https://studio.iterative.ai/auth/device-login?code=Z7JDECGR

Once you've logged in, return here and you'll be ready to start the experiments.

Failed to open a web browser. Open the above url to continue in your web browser.

Expected

The login command should produce a link to the server specified by studio.url, as described in the docs.

Environment information

Output of dvc doctor:

$ dvc doctor
DVC version: 3.50.1 (pip)
-------------------------
Platform: Python 3.10.12 on Linux-6.5.0-1022-oem-x86_64-with-glibc2.35
Subprojects:
    dvc_data = 3.15.1
    dvc_objects = 5.1.0
    dvc_render = 1.0.2
    dvc_task = 0.4.0
    scmrepo = 3.3.2
Supports:
    http (aiohttp = 3.9.5, aiohttp-retry = 2.8.3),
    https (aiohttp = 3.9.5, aiohttp-retry = 2.8.3),
    s3 (s3fs = 2024.3.1, boto3 = 1.34.69)
Config:
    Global: /home/george/.config/dvc
    System: /etc/xdg/xdg-ubuntu/dvc
Cache types: hardlink, symlink
Cache directory: ext4 on /dev/mapper/vgubuntu-root
Caches: local
Remotes: local, s3
Workspace directory: ext4 on /dev/mapper/vgubuntu-root
Repo: dvc, git
Repo.site_cache_dir: /var/tmp/dvc/repo/b380dbe5c5355f17c427aac92d8f5759