Build events-log plugin for all maintained branches

Events-log plugin was built exclusively for gerrit 3.10 and master.
Since 3.10 is officially EOL, build it instead for all maintaned
branches: 3.11, 3.12, 3.13.

Change-Id: I5149232a68d8bdf8800ce620b7d33d7236d253e9

jenkins/gerrit-bazel-plugin-events-log.yaml

diff --git a/jenkins/gerrit-bazel-plugin-events-log.yaml b/jenkins/gerrit-bazel-plugin-events-log.yaml
index 033fcc4..9bb807b 100644
--- a/jenkins/gerrit-bazel-plugin-events-log.yaml
+++ b/jenkins/gerrit-bazel-plugin-events-log.yaml
@@ -1,9 +1,13 @@
 - project:
     name: events-log
     jobs:
+      - 'plugin-{name}-bazel-{branch}':
+          branch:
+            - master
       - 'plugin-{name}-bazel-{branch}-{gerrit-branch}':
           branch:
             - master
           gerrit-branch:
-            - master
-            - stable-3.10
+            - stable-3.13
+            - stable-3.12
+            - stable-3.11