docs: add links to the CHANGELOG from the README.md for Java and Node (#420)

This PR was generated using Autosynth. 🌈

Synth log will be available here:
https://source.cloud.google.com/results/invocations/7b446397-88f3-4463-9e7d-d2ce7069989d/targets

- [ ] To automatically regenerate this PR, check this box.

Source-Link: googleapis/synthtool@5936421

Author: yoshi-automation

packages/google-cloud-dataproc/README.md

@@ -14,6 +14,9 @@
 Google Cloud Dataproc API client for Node.js
 
 
+A comprehensive list of changes in each version may be found in
+[the CHANGELOG](https://github.com/googleapis/nodejs-dataproc/blob/master/CHANGELOG.md).
+
 * [Google Cloud Dataproc Node.js Client API Reference][client-docs]
 * [Google Cloud Dataproc Documentation][product-docs]
 * [github.com/googleapis/nodejs-dataproc](https://github.com/googleapis/nodejs-dataproc)

packages/google-cloud-dataproc/synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/nodejs-dataproc.git",
-        "sha": "2fce24a1ff5f37fde9464abafa367faf0399e5f8"
+        "sha": "da36cccb0b3267953dafa78208706a129062f907"
       }
     },
     {
@@ -19,7 +19,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "89d431fb2975fc4e0ed24995a6e6dfc8ff4c24fa"
+        "sha": "5936421202fb53ed4641bcb824017dd393a3dbcc"
       }
     }
   ],