feat(nix/buildkite): add meta.ci.buildkiteExtraStepArgs r/6443

This allows setting / overwriting arbitrary step arguments, such as setting
[Retry attributes](https://buildkite.com/docs/pipelines/command-step#retry-attributes)
for a specific readTree target.

It's intended to be used for cases where modelling each and every option
in a custom meta.ci attribute would be unfeasible.

Change-Id: I3352d5353b26a41a16760a7df37cd5ffee1665bb
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8983
Autosubmit: flokli <flokli@flokli.de>
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI

0 files changed, 0 insertions, 0 deletions