Only update/override powershell module path when in CI on module script import (#3791)

Co-authored-by: Ben Broderick Phillips <bebroder@microsoft.com>

eng/common/scripts/Helpers/PSModule-Helpers.ps1

@@ -1,7 +1,7 @@
 $DefaultPSRepositoryUrl = "https://www.powershellgallery.com/api/v2"
 $global:CurrentUserModulePath = ""
 
-function Update-PSModulePath()
+function Update-PSModulePathForCI()
 {
   # Information on PSModulePath taken from docs
   # https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_psmodulepath
@@ -101,4 +101,6 @@ function Install-ModuleIfNotInstalled()
   return $modules[0]
 }
 
-Update-PSModulePath
+if ($null -ne $env:SYSTEM_TEAMPROJECTID) {
+    Update-PSModulePathForCI
+}