chore: copy README to docfx-yml dir (#937)

This PR was generated using Autosynth. 🌈 Synth log will be available here: https://source.cloud.google.com/results/invocations/55f460c4-bcb1-4d76-b766-e2a8c306b9e5/targets - [ ] To automatically regenerate this PR, check this box. 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

@@ -4,7 +4,7 @@
  "git": {
  "name": ".",
  "remote": "https://github.com/googleapis/java-spanner.git",
- "sha": "0d93d92fcd7c8bb2ffd3198560c4be3e4afc4990"
+ "sha": "0db6746f885dc70875d228beb8f0468d1ce25447"
  }
  },
  {
@@ -19,7 +19,7 @@
  "git": {
  "name": "synthtool",
  "remote": "https://github.com/googleapis/synthtool.git",
- "sha": "21da7d9fa02f6916d9f87cf4072b3547b5c72eb5"
+ "sha": "d0bdade9a962042dc0f770cf631086f3db59b5b0"
  }
  }
  ],