Change default branch to 'main' from 'master' for ETOS

Change-Id: Ib2a8b3ea05d930a664f64eb0dfae16d9bfe14a07
diff --git a/jjb/eiffel/etos-test-runner-containers-go.yaml b/jjb/eiffel/etos-test-runner-containers-go.yaml
index ca66201..7a8d67d 100644
--- a/jjb/eiffel/etos-test-runner-containers-go.yaml
+++ b/jjb/eiffel/etos-test-runner-containers-go.yaml
@@ -26,8 +26,8 @@
 
 
     stream:
-      - 'master':
-          branch: 'master'
+      - 'main':
+          branch: 'main'
           project-git-repo: 'etos-test-runner-containers'
           project-build-macro: 'eiffel-global-container-build-macro'
           image-dockerfile: 'go/Dockerfile'