PnP PowerShell Upgrade Error - "Authenticode issuer" certificate invalid

With the December 2017 release SharePoint PnP PowerShell, if you update the PnP PowerShell commendlets using “Update-Module” via PowerShell, you might receive the following error.

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PackageManagement\Install-Package : Authenticode issuer 'CN=Microsoft Root Certificate Authority 2011, O=Microsoft Corporation, L=Redmond, S=Washington, C=US' of the new module
'SharePointPnPPowerShellOnline' with version '2.21.1712.2' is not matching with the authenticode issuer 'CN=thawte Primary Root CA, OU="(c) 2006 thawte, Inc. - For authorized use only",
OU=Certification Services Division, O="thawte, Inc.", C=US' of the previously-installed module 'SharePointPnPPowerShellOnline' with version '2.20.1711.0'. If you still want to install or
update, use -SkipPublisherCheck parameter.
At C:\Program Files\WindowsPowerShell\Modules\PowerShellGet\1.0.0.1\PSModule.psm1:2089 char:20
+ ... $sid = PackageManagement\Install-Package @PSBoundParameters
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidOperation: (Microsoft.Power....InstallPackage:InstallPackage) [Install-Package], Exception
+ FullyQualifiedErrorId : AuthenticodeIssuerMismatch,Validate-ModuleAuthenticodeSignature,Microsoft.PowerShell.PackageManagement.Cmdlets.InstallPackage

What Happened?

Real simple here, with the December 2017 release, new signing certificates where used, so we cannot simply “update”, rather we need to uninstall and re-install.

Open PowerShell as an admininistrator.
*Optional: Check to see what PnP module(s) may be installed.
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Get-Module SharePointPnPPowerShell* -ListAvailable | Select-Object Name,Version | Sort-Object Version –Descending
Uninstall PnP PowerShell
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Uninstall-Module SharePointPnPPowerShellOnline
*Optional: Check again to verify that the module(s) have been removed
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Get-Module SharePointPnPPowerShell* -ListAvailable | Select-Object Name,Version | Sort-Object Version –Descending
Install the latest version of PnP PowerShell
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Install-Module SharePointPnPPowerShellOnline