Docs check is failing on CI

[jtpio]

Noticed in #7321.

The docs check seems to be failing: https://github.com/jupyter/notebook/actions/runs/8816599078/job/24201068166?pr=7321

Run sudo apt-get update
+ sudo apt-get update
Get:1 https://packages.microsoft.com/ubuntu/22.04/prod jammy InRelease
Err:1 https://packages.microsoft.com/ubuntu/22.04/prod jammy InRelease
  Clearsigned file isn't valid, got 'NOSPLIT' (does the network require authentication?)
Get:2 file:/etc/apt/apt-mirrors.txt Mirrorlist [142 B]
Hit:3 http://azure.archive.ubuntu.com/ubuntu jammy InRelease
Get:4 http://azure.archive.ubuntu.com/ubuntu jammy-updates InRelease [119 kB]
Get:5 http://azure.archive.ubuntu.com/ubuntu jammy-backports InRelease [109 kB]
Get:6 http://azure.archive.ubuntu.com/ubuntu jammy-security InRelease [110 kB]
Hit:7 https://ppa.launchpadcontent.net/ubuntu-toolchain-r/test/ubuntu jammy InRelease
Get:8 http://azure.archive.ubuntu.com/ubuntu jammy-updates/main amd64 Packages [1610 kB]
Get:9 http://azure.archive.ubuntu.com/ubuntu jammy-updates/main Translation-en [303 kB]
Get:10 http://azure.archive.ubuntu.com/ubuntu jammy-updates/restricted amd64 Packages [1830 kB]
Get:11 http://azure.archive.ubuntu.com/ubuntu jammy-updates/restricted Translation-en [311 kB]
Get:12 http://azure.archive.ubuntu.com/ubuntu jammy-updates/universe amd64 Packages [1070 kB]
Get:13 http://azure.archive.ubuntu.com/ubuntu jammy-updates/universe Translation-en [244 kB]
Get:14 http://azure.archive.ubuntu.com/ubuntu jammy-backports/universe amd64 Packages [27.2 kB]
Get:15 http://azure.archive.ubuntu.com/ubuntu jammy-backports/universe Translation-en [16.2 kB]
Get:16 http://azure.archive.ubuntu.com/ubuntu jammy-security/main amd64 Packages [1392 kB]
Get:17 http://azure.archive.ubuntu.com/ubuntu jammy-security/main Translation-en [243 kB]
Get:18 http://azure.archive.ubuntu.com/ubuntu jammy-security/restricted amd64 Packages [1768 kB]
Get:19 http://azure.archive.ubuntu.com/ubuntu jammy-security/restricted Translation-en [299 kB]
Get:20 http://azure.archive.ubuntu.com/ubuntu jammy-security/universe amd64 Packages [848 kB]
Get:21 http://azure.archive.ubuntu.com/ubuntu jammy-security/universe Translation-en [163 kB]
Reading package lists...
E: Failed to fetch https://packages.microsoft.com/ubuntu/22.04/prod/dists/jammy/InRelease  Clearsigned file isn't valid, got 'NOSPLIT' (does the network require authentication?)
E: The repository 'https://packages.microsoft.com/ubuntu/22.04/prod jammy InRelease' is no longer signed.
Error: Process completed with exit code 100.

[jtpio]

Looks like this is not an issue anymore, as the check passes in #7346 without doing anything.