User Story 37654: Create Extensions base package

- Using ADO-specific Linux image.
- Fixed typo in dotnet restore arguments.

Author: paulmedynski

eng/pipelines/stages/ci-build-extensions-package-stage.yml

@@ -53,15 +53,15 @@ parameters:
 
 stages:
   - stage: extensions_package_stage
-    displayName: CI Stage for Extensions Package
+    displayName: Build Extensions Package
 
     jobs:
 
     - job: extensions_package_job
-      displayName: CI Job for Extensions Package
+      displayName: Build Extensions Package
       pool:
         name: ADO-CI-1ES-Pool
-        vmImage: ubuntu-latest
+        vmImage: ADO-UB20-SQL22
 
       variables:
         # The directory where dotnet artifacts will be staged.  Not to be
@@ -107,7 +107,7 @@ stages:
           command: custom
           custom: restore
           projects: $(project)
-          arguments: $(commonArtifacts)
+          arguments: $(commonArguments)
 
       - task: DotNetCoreCLI@2
         displayName: Build Solution