chore: copy README to docfx-yml dir (googleapis#382)

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Source-Link: googleapis/synthtool@d0bdade

Author: yoshi-automation

.kokoro/release/publish_javadoc11.sh

@@ -40,6 +40,9 @@ export VERSION=$(grep ${NAME}: versions.txt | cut -d: -f3)
 # generate yml
 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
+
 pushd target/docfx-yml
 
 # create metadata
@@ -52,4 +55,4 @@ python3 -m docuploader create-metadata \
 python3 -m docuploader upload . \
  --credentials ${CREDENTIALS} \
  --staging-bucket ${STAGING_BUCKET_V2} \
- --destination-prefix docfx-
+ --destination-prefix docfx

synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-spanner-jdbc.git",
-        "sha": "4cbee6dcc2dfea2515437b55b0ecfc956205d739"
+        "sha": "f18abc9361c1f3535c5fdec8eee45dd1fb821334"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "21da7d9fa02f6916d9f87cf4072b3547b5c72eb5"
+        "sha": "d0bdade9a962042dc0f770cf631086f3db59b5b0"
       }
     }
   ],