Remove default value for pipeline picklist params (#7357)

* Parameters passed from powerapps are accessible as variables only

eng/pipelines/devops-create-package-workitem.yml

@@ -5,7 +5,7 @@ pool:
 parameters:
 - name: Language
   type: string
-  default: ''
+  default: '.NET'
   values:
   - .NET
   - Java
@@ -24,7 +24,7 @@ parameters:
   default: ''
 - name: PackageType
   type: string
-  default: ''
+  default: 'Client'
   values:
   - Client
   - mgmt
@@ -58,13 +58,13 @@ steps:
     pwsh: true
     filePath: $(Build.SourcesDirectory)/eng/common/scripts/Update-DevOps-Release-WorkItem.ps1
     arguments: >
-      -language "${{parameters.Language}}"
-      -serviceName "${{parameters.ServiceName}}"
-      -packageDisplayName "${{parameters.PackageDisplayName}}"
-      -packageType "${{parameters.PackageType}}"
-      -packageName "${{parameters.PackageName}}"
-      -version "${{parameters.PackageVersion}}"
-      -plannedDate "${{parameters.ReleaseDate}}"
-      -relatedWorkItemId ${{parameters.RelatedWorkItemId}}
-      -tag "${{parameters.Tag}}"
+      -language "$(Language)"
+      -serviceName "$(ServiceName)"
+      -packageDisplayName "$(PackageDisplayName)"
+      -packageType "$(PackageType)"
+      -packageName "$(PackageName)"
+      -version "$(PackageVersion)"
+      -plannedDate "$(ReleaseDate)"
+      -relatedWorkItemId "$(RelatedWorkItemId)"
+      -tag "$(Tag)"
       -devops_pat "$(azuresdk-azure-sdk-devops-release-work-item-pat)"