Updated ci jobs

Author: delvedor

.ci/jobs/elastic+elasticsearch-js+5.x.yml

@@ -0,0 +1,13 @@
+---
+- job:
+    name: elastic+elasticsearch-js+5.x
+    display-name: 'elastic / elasticsearch-js # 5.x'
+    description: Testing the elasticsearch-js 5.x branch.
+    parameters:
+    - string:
+        name: branch_specifier
+        default: refs/heads/5.x
+        description: the Git branch specifier to build (<branchName>, <tagName>,
+          <commitId>, etc.)
+    triggers:
+    - timed: '@weekly'

.ci/jobs/elastic+elasticsearch-js+6.x.yml

@@ -9,3 +9,5 @@
         default: refs/heads/6.x
         description: the Git branch specifier to build (<branchName>, <tagName>,
           <commitId>, etc.)
+    triggers:
+    - timed: '@weekly'

.ci/jobs/elastic+elasticsearch-js+7.x.yml

@@ -9,3 +9,5 @@
         default: refs/heads/7.x
         description: the Git branch specifier to build (<branchName>, <tagName>,
           <commitId>, etc.)
+    triggers:
+    - timed: '@weekly'