Update build-all-steps.yml (#18772)

* Update build-all-steps.yml

Author: qianz2

ci/build-all-steps.yml

@@ -21,6 +21,12 @@ steps:
   inputs:
     versionSpec: 10.x
 
+# Use .NET SDK 7
+- task: UseDotNet@2
+  displayName: 'Install .NET Core SDK 7.x'
+  inputs:
+    version: 7.x
+
 # npm install
 - script: npm install
   displayName: npm install
@@ -187,4 +193,4 @@ steps:
         eq(variables['COURTESY_PUSH'], 'true'),
         eq(variables['Build.SourceBranch'], 'refs/heads/master')
       )
-    displayName: Create Release
+    displayName: Create Release