Build SAML plugin on stable-3.1[1-3]

Change-Id: I1ad0a65a0f040ccf362ed3dbfa27808e4c1d6c6b

jenkins/gerrit-plugin-saml.yaml

diff --git a/jenkins/gerrit-plugin-saml.yaml b/jenkins/gerrit-plugin-saml.yaml
index db8236d..95c5025 100644
--- a/jenkins/gerrit-plugin-saml.yaml
+++ b/jenkins/gerrit-plugin-saml.yaml
@@ -4,11 +4,11 @@
       - 'plugin-{name}-bazel-{branch}':
           branch:
             - master
+            - stable-3.13
+            - stable-3.12
+            - stable-3.11
       - 'plugin-{name}-bazel-{branch}-{gerrit-branch}':
           branch:
             - master
           gerrit-branch:
             - stable-3.14
-            - stable-3.13
-            - stable-3.12
-            - stable-3.11