Build its-base and its-jira plugins for Gerrit v3.11 and v3.12

Change-Id: I117cc8cbd0792f7008d9b16b98c43c06ba42b658
diff --git a/jenkins/gerrit-bazel-plugin-its-base.yaml b/jenkins/gerrit-bazel-plugin-its-base.yaml
index 1c3c4f0..630c677 100644
--- a/jenkins/gerrit-bazel-plugin-its-base.yaml
+++ b/jenkins/gerrit-bazel-plugin-its-base.yaml
@@ -5,6 +5,8 @@
           branch:
             - master
           gerrit-branch:
+            - stable-3.12
+            - stable-3.11
             - stable-3.10
           targets: 'plugins/its-base:its-base plugins/its-base:its_base_tests'
       - 'plugin-{name}-bazel-{branch}':
diff --git a/jenkins/gerrit-bazel-plugin-its-jira.yaml b/jenkins/gerrit-bazel-plugin-its-jira.yaml
index a69e6e5..60169f7 100644
--- a/jenkins/gerrit-bazel-plugin-its-jira.yaml
+++ b/jenkins/gerrit-bazel-plugin-its-jira.yaml
@@ -5,6 +5,8 @@
           branch:
             - master
           gerrit-branch:
+            - stable-3.12
+            - stable-3.11
             - stable-3.10
           targets: 'plugins/its-jira:its-jira plugins/its-jira:its_jira_tests'
       - 'plugin-its-{name}-bazel-{branch}':