Fixing some piping issue. https://github.com/Azure/azure-powershell/issues/2996

[diwudd]

Description

The issue was when removing a set of resources, if one of operations failed, the following ones also failed because the "cancellationSource" was set to null by the first failed operation. By reinitializing "cancellationSource", we make the operations "stateless" even in pipeline.

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[azuresdkci]

Can one of the admins verify this patch?

[vivsriaus]

@diwudd can we please add a scenario test for this?

[shahabhijeet]

@azuresdkci add to whitelist

[shahabhijeet]

@vivsriaus can you review this change

[vivsriaus]

@azuresdkci retest this please

[diwudd]

@azuresdkci retest this please

[TianoMS]

Is the change covered by these two test cases?

[diwudd]

This is the scenario test I added and recorded.

[vivsriaus]

LGTM

[cormacpayne]

@TianoMS Hey Tian, do you sign-off on these changes?

[TianoMS]

@cormacpayne Signed off.

[markcowl]

on demand run here:http://azuresdkci.cloudapp.net/view/1-AzurePowerShell/job/powershell-demand/1255/

LGTM once the on-demand build passes