Build the gc-conductor plugin for 2.14 and 2.15

Change-Id: I2e287cb286cbbcba8f85a18824a2a99b5d3e215f
diff --git a/jenkins/gerrit-bazel-plugin-gc-conductor.yaml b/jenkins/gerrit-bazel-plugin-gc-conductor.yaml
new file mode 100644
index 0000000..8edd696
--- /dev/null
+++ b/jenkins/gerrit-bazel-plugin-gc-conductor.yaml
@@ -0,0 +1,7 @@
+- project:
+    name: gc-conductor
+    jobs:
+      - 'plugin-{name}-bazel-{branch}':
+          branch:
+            - stable-2.15
+            - stable-2.14