package buildbot is broken on aarch64

[seese]

Issue description

Package buildbot is broken on aarch64 because some tests are aborted with TimeoutErrors.

buildbot.log

https://hydra.nixos.org/build/72891629/nixlog/1

Steps to reproduce

Try to install/build it on a Raspberry Pi 3.

Technical details

$ nix-shell -p nix-info --run "nix-info -m"

• system: "aarch64-linux"
• host os: Linux 4.15.18, NixOS, 18.03.132192.ce0d9d638de (Impala)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.0.1
• channels(root): "nixos-18.03.132192.ce0d9d638de"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs

[seese]

For me it is possible to build it on aarch64 with a docheck = false.

What also works is to patch file monkeypatches/init.py -> method patch_testcase_timeout.

If unittest.TestCase.timeout = 5 is changed to the value 120, it installs without problems.

So, what is the best strategy to work around that problem?