Merge branch 'release/3.1' into dougbu/3.1/newer.agents.3540

- fixup one more agent request
- nit: Consistently use `in` / `notin` with `Build.Reason`
  - YAML was inconsistent and this aligns w/ the Arcade code

Author: dougbu

.azure/pipelines/benchmarks.yml

@@ -0,0 +1,18 @@
+# This configuration builds the repository and runs benchmarks
+
+# Don't run CI for this config
+trigger: none
+
+pr:
+- '*'
+
+jobs:
+- template: jobs/default-build.yml
+  parameters:
+    jobName: Windows_Build
+    jobDisplayName: "Build only : Windows"
+    agentOs: Windows
+    buildArgs: -ci -all -pack
+    artifacts:
+    - path: artifacts/
+      includeForks: true