Extend Unofficial 1ES template in IdentityModel nightly tests job (#63465)

Co-authored-by: William Godbe <[email protected]>

.azure/pipelines/identitymodel-helix-matrix.yml

@@ -26,7 +26,7 @@ resources:
     ref: refs/tags/release
 
 extends:
-  template: v1/1ES.Official.PipelineTemplate.yml@1esPipelines
+  template: v1/1ES.Unofficial.PipelineTemplate.yml@1esPipelines
   parameters:
     sdl:
       sourceAnalysisPool: