fix: use stash/unstash for expose-daemon.ps1 instead of fetching via http

[doodlesbykumbi]

NOTES:

1. The build was failing on attempting to fetch a file via http with the following error. (see https://jenkins.conjur.net/blue/organizations/jenkins/cyberark--conjur-puppet/detail/fix/1/pipeline/48)

   [2021-01-25T15:56:52.845Z] powershell.exe : Invoke-WebRequest : The request was aborted: Could not create SSL/TLS secure channel.
   [2021-01-25T15:56:52.845Z] At C:\jenkins\workspace\cyberark--conjur-puppet_fix@tmp\durable-04aa52cf\powershellWrapper.ps1:3 char:1
   [2021-01-25T15:56:52.845Z] + & powershell -NoProfile -NonInteractive -ExecutionPolicy Bypass -Comm ...
   [2021-01-25T15:56:52.845Z] + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   [2021-01-25T15:56:52.845Z]     + CategoryInfo          : NotSpecified: (Invoke-WebReque...secure channel.:String) [], RemoteException
   [2021-01-25T15:56:52.845Z]     + FullyQualifiedErrorId : NativeCommandError
   [2021-01-25T15:56:52.845Z]
   [2021-01-25T15:56:52.845Z] At C:\jenkins\workspace\cyberark--conjur-puppet_fix@tmp\durable-04aa52cf\powershellScript.ps1:2 char:19
   [2021-01-25T15:56:52.845Z] + ...             Invoke-WebRequest -Uri "https://raw.githubusercontent.com ...
   [2021-01-25T15:56:52.845Z] +                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   [2021-01-25T15:56:52.845Z]     + CategoryInfo          : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest) [Invoke-WebRequest], WebExc
   [2021-01-25T15:56:52.845Z]
   [2021-01-25T15:56:52.845Z]    eption
   [2021-01-25T15:56:52.845Z]
   [2021-01-25T15:56:52.845Z]     + FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeWebRequestCommand

2. Any powershell invocation seem to fail silently, see https://github.com/cyberark/conjur-puppet/blob/master/Jenkinsfile#L48. You can also consult the failing build from (1) to see what I mean. I'm sure there's a way to make them fail on error.

   What does this PR do?

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What ticket does this PR close?

Resolves #249

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