build: Add docuploader credentials to node publish jobs (#322)

Author: jkwlui

.kokoro/release/publish.cfg

@@ -18,6 +18,15 @@ before_action {
   }
 }
 
+before_action {
+  fetch_keystore {
+    keystore_resource {
+      keystore_config_id: 73713
+      keyname: "docuploader_service_account"
+    }
+  }
+}
+
 # Fetch magictoken to use with Magic Github Proxy 
 before_action {
   fetch_keystore {

synth.metadata

@@ -1,11 +1,11 @@
 {
-  "updateTime": "2019-03-05T12:13:36.921240Z",
+  "updateTime": "2019-03-08T00:45:38.322552Z",
   "sources": [
     {
       "template": {
         "name": "node_library",
         "origin": "synthtool.gcp",
-        "version": "2019.2.26"
+        "version": "2019.1.16"
       }
     }
   ]