fa964ab (in #565) was incorrect.

jglick · MarkEWaite · commit 9e8621eca638 · 2018-05-19T18:12:10.000-06:00
jenkinsci/jenkins@6bb85ec went into 2.122, not 2.121.
diff --git a/essentials.yml b/essentials.yml
@@ -1,7 +1,7 @@
 ---
 ath:
   athRevision: "dad333092159cb368efc2f9869572f0a05d255ac"
-  jenkins: "2.121-rc15727.3b61b96119b9"
+  jenkins: "2.122"
   tests:
     - "GitPluginTest"
     - "GitUserContentTest"
