CI pipelines stuck in pending

[aaronmarkham]

Description

EDIT: I reported this originally as the website pipeline getting stuck, but it isn't limited to that.
I have seen this a couple of times now so I'm going to leave the PR it this hanging state so it can be investigated.
#13705
You can see the CI pipeline here - it seems completed and successful, but Jenkins thinks it is still pending.
Docs pipeline that was stuck:
http://jenkins.mxnet-ci.amazon-ml.com/blue/organizations/jenkins/mxnet-validation%2Fwebsite/detail/PR-13705/1/pipeline/74
GPU pipeline that was stuck:
http://jenkins.mxnet-ci.amazon-ml.com/blue/organizations/jenkins/mxnet-validation%2Fwindows-gpu/detail/PR-13860/1/pipeline

[aaronmarkham]

Not sure if this is related... the CI process hangs even after an apparently successful run on the edge pipeline.
http://jenkins.mxnet-ci.amazon-ml.com/blue/organizations/jenkins/mxnet-validation%2Fedge/detail/PR-13725/1/pipeline