azure-pipelines: move to new MicroBuild pool

Move from the VSEngSS-MicroBuild2022-1ES pool to the new
VSEng-MicroBuildVSStable pool, which has Windows Server 2025
+ Visual Studio 2026 images instead.

Signed-off-by: Matthew John Cheetham <mjcheetham@outlook.com>

Author: mjcheetham

.azure-pipelines/release.yml

@@ -25,7 +25,7 @@ extends:
   template: azure-pipelines/MicroBuild.1ES.Official.yml@MicroBuildTemplate
   parameters:
     pool:
-      name: VSEngSS-MicroBuild2022-1ES
+      name: VSEng-MicroBuildVSStable
 
     featureFlags:
       incrementalSDLBinaryAnalysis: false