fix: add missing image and enable Go module proxy in daily CI build

Added missing image: ubuntu-latest to pool config and enabled
featureFlags.golang.internalModuleProxy to opt in to Microsoft's
internal Go module proxy (required after August 2025).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: ramsessanchez

.azure-pipelines/daily-ci-build.yml

@@ -21,7 +21,12 @@ extends:
   parameters:
     pool:
       name: Azure-Pipelines-1ESPT-ExDShared
+      image: ubuntu-latest
       os: linux
+    featureFlags:
+      golang:
+        internalModuleProxy:
+          enabled: true
     sdl:
       sourceAnalysisPool:
         name: Azure-Pipelines-1ESPT-ExDShared