chore: add changelog to cloud-rad (#214)

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Source-Link: googleapis/synthtool@c86c7a6

Author: yoshi-automation

.kokoro/release/publish_javadoc11.sh

@@ -42,6 +42,8 @@ mvn clean site -B -q -P docFX
 
 # copy README to docfx-yml dir and rename index.md
 cp README.md target/docfx-yml/index.md
+# copy CHANGELOG to docfx-yml dir and rename history.md
+cp CHANGELOG.md target/docfx-yml/history.md
 
 pushd target/docfx-yml
 

synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-dialogflow-cx.git",
-        "sha": "0ae811ac66d6720d5d6d13eda8b124a2bf8f14a2"
+        "sha": "373493ae1a383d498fa365252b4c447fc3e1317c"
       }
     },
     {
@@ -27,7 +27,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "4f4b1b9b8d8b52f1e9e4a76165896debce5ab7f1"
+        "sha": "c86c7a60985644eab557949363a38301d40d78d2"
       }
     }
   ],