docs: add links to the CHANGELOG from the README.md for Java and Node (…

…#378)

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Source-Link: googleapis/synthtool@5936421

packages/google-cloud-iot/README.md

@@ -16,6 +16,9 @@
 [Google Cloud Internet of Things (IoT) Core](https://cloud.google.com/iot/docs) is a fully managed service for securely connecting and managing IoT devices, from a few to millions. Ingest data from connected devices and build rich applications that integrate with the other big data services of Google Cloud Platform.
 
 
+A comprehensive list of changes in each version may be found in
+[the CHANGELOG](https://github.com/googleapis/nodejs-iot/blob/master/CHANGELOG.md).
+
 * [Google Cloud Internet of Things (IoT) Core Node.js Client API Reference][client-docs]
 * [Google Cloud Internet of Things (IoT) Core Documentation][product-docs]
 * [github.com/googleapis/nodejs-iot](https://github.com/googleapis/nodejs-iot)

packages/google-cloud-iot/synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/nodejs-iot.git",
-        "sha": "d364f0019ab0f2a671c854edc24e57135b90883f"
+        "sha": "6dc6d7c7f7baf485a0c9bb5c64319ec35b114a46"
       }
     },
     {
@@ -19,7 +19,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "89d431fb2975fc4e0ed24995a6e6dfc8ff4c24fa"
+        "sha": "5936421202fb53ed4641bcb824017dd393a3dbcc"
       }
     }
   ],