azure pipelines restart failed job

[timotheecour]

this should be in https://nim-lang.github.io/Nim/contributing.html :
restarting a failed job (eg bc of a flaky test) on azure pipelines can be done as follows:

• if on your own fork, it's possible from inside azure console (eg https://dev.azure.com/timotheecour/timotheecour/_build/results?buildId=1430&view=results) via "rerun failed jobs"
• if either on you own fork on in Nim repo, it's possible from inside github UI under checks tab, see azure pipelines restart failed job #211 (comment)

on my nim fork:

on nim repo:

[timotheecour]

[ringabout]

already fixed