Revert move to VS2019.Pre queues

This reverts part of commit b67d161
- was "[release/5.0-preview5] Update dependencies from dotnet/aspnetcore-tooling (#21710)"

Author: dougbu

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

@@ -104,11 +104,16 @@ jobs:
       ${{ if eq(parameters.agentOs, 'Windows') }}:
         ${{ if eq(variables['System.TeamProject'], 'public') }}:
           name: NetCorePublic-Pool
-          queue: BuildPool.Windows.10.Amd64.VS2019.Pre.Open
+          ${{ if ne(parameters.isTestingJob, true) }}:
+            # Visual Studio Build Tools
+            queue: BuildPool.Server.Amd64.VS2019.BT.Open
+          ${{ if eq(parameters.isTestingJob, true) }}:
+            # Visual Studio Enterprise - contains some stuff, like SQL Server and IIS Express, that we use for testing
+            queue: BuildPool.Server.Amd64.VS2019.Open
         ${{ if eq(variables['System.TeamProject'], 'internal') }}:
           name: NetCoreInternal-Pool
           # Visual Studio Enterprise - contains some stuff, like SQL Server and IIS Express, that we use for testing
-          queue: BuildPool.Windows.10.Amd64.VS2019.Pre
+          queue: BuildPool.Server.Amd64.VS2019
     variables:
     - AgentOsName: ${{ parameters.agentOs }}
     - ASPNETCORE_TEST_LOG_MAXPATH: "200" # Keep test log file name length low enough for artifact zipping