fix(powershell): use azdo provided OIDC url variable (#584)

Allows the task to be used in release pipelines. Without this change, the url only applies to build pipelines.

* fix oidc request url for PowerShell Module

* use the correct OIDC request url

* add changelog

---------

Co-authored-by: Marian Epure <marian.epure@888holdings.com>

Author: jedimanu-ux

.changes/next-release/Bug Fix-4c8c9cea-b7f9-407b-b85e-36fdba5fc17b.json

@@ -0,0 +1,4 @@
+{
+	"type": "Bug Fix",
+	"description": "use the correct OIDC request url for the PowerShell task"
+}

src/tasks/AWSPowerShellModuleScript/RunAWSPowerShellModuleScript.ps1

@@ -116,7 +116,7 @@ try {
                 }
 
                 # Request an OIDC token for the service connection from the VSTS REST API
-                $url = "$Env:SYSTEM_TEAMFOUNDATIONCOLLECTIONURI$Env:SYSTEM_TEAMPROJECTID/_apis/distributedtask/hubs/build/plans/$Env:SYSTEM_PLANID/jobs/$Env:SYSTEM_JOBID/oidctoken?api-version=7.1-preview.1&serviceConnectionId=$awsEndpoint"
+                $url = $Env:SYSTEM_OIDCREQUESTURI + "?api-version=7.1-preview.1&serviceConnectionId=$awsEndpoint"
                 $response = Invoke-WebRequest -Uri $url -Method POST -Headers $Headers  -Body '{}' -ContentType "application/json" | ConvertFrom-Json
                 $token = $response.oidcToken