Change 7.x Jenkins job to 7.16

Author: sethmlarson

.ci/jobs/elastic+elasticsearch-py+7.x.yml renamed to .ci/jobs/elastic+elasticsearch-py+7.16.yml

@@ -1,12 +1,12 @@
 ---
 - job:
-    name: elastic+elasticsearch-py+7.x
-    display-name: 'elastic / elasticsearch-py # 7.x'
-    description: Testing the elasticsearch-py 7.x branch.
+    name: elastic+elasticsearch-py+7.16
+    display-name: 'elastic / elasticsearch-py # 7.16'
+    description: Testing the elasticsearch-py 7.16 branch.
     junit_results: "*-junit.xml"
     parameters:
     - string:
         name: branch_specifier
-        default: refs/heads/7.x
+        default: refs/heads/7.16
         description: the Git branch specifier to build (<branchName>, <tagName>,
           <commitId>, etc.)