Update default-build.yml

.azure/pipelines/jobs/default-build.yml

@@ -105,10 +105,10 @@ jobs:
         ${{ if eq(parameters.useHostedUbuntu, false) }}:
           ${{ if eq(variables['System.TeamProject'], 'public') }}:
             name: NetCorePublic-Pool
-            queue: Ubuntu.1804.Amd64.Open
+            queue: BuildPool.Ubuntu.1604.Amd64.Open
           ${{ if eq(variables['System.TeamProject'], 'internal') }}:
             name: NetCoreInternal-Pool
-            queue: Ubuntu.1804.Amd64
+            queue: BuildPool.Ubuntu.1604.Amd64
       ${{ if eq(parameters.agentOs, 'Windows') }}:
         ${{ if eq(variables['System.TeamProject'], 'public') }}:
           name: NetCorePublic-Pool