chore: remove docLava v2 doc generation (googleapis#474)

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Source-Link: googleapis/synthtool@21da7d9

.kokoro/release/publish_javadoc.cfg

@@ -7,12 +7,6 @@ env_vars: {
   value: "docs-staging"
 }
 
-# cloud-rad staging
-env_vars: {
-  key: "STAGING_BUCKET_V2"
-  value: "docs-staging-v2-staging"
-}
-
 env_vars: {
   key: "TRAMPOLINE_BUILD_FILE"
   value: "github/java-storage-nio/.kokoro/release/publish_javadoc.sh"
@@ -26,4 +20,4 @@ before_action {
       keyname: "docuploader_service_account"
     }
   }
-}
+}

.kokoro/release/publish_javadoc.sh

@@ -56,22 +56,3 @@ python3 -m docuploader create-metadata \
 python3 -m docuploader upload . \
   --credentials ${CREDENTIALS} \
   --staging-bucket ${STAGING_BUCKET}
-
-popd
-
-# V2 due to problems w/ the released javadoc plugin doclava, Java 8 is required.  Beware of accidental updates.
-
-mvn clean site -B -q -Ddevsite.template="${KOKORO_GFILE_DIR}/java/"
-
-pushd target/devsite/reference
-
-# create metadata
-python3 -m docuploader create-metadata \
-  --name ${NAME} \
-  --version ${VERSION} \
-  --language java
-
-# upload docs to staging bucket
-python3 -m docuploader upload . \
-  --credentials ${CREDENTIALS} \
-  --staging-bucket ${STAGING_BUCKET_V2}

synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-storage-nio.git",
-        "sha": "21369c213498127a6e4561dc2faa836b01c5c08f"
+        "sha": "c687c489b8d4913a6a5b42082c9b9404055613ba"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "6946fd71ae9215b0e7ae188f5057df765ee6d7d2"
+        "sha": "21da7d9fa02f6916d9f87cf4072b3547b5c72eb5"
       }
     }
   ],
@@ -32,7 +32,6 @@
     ".github/workflows/ci.yaml",
     ".github/workflows/samples.yaml",
     ".kokoro/build.bat",
-    ".kokoro/build.sh",
     ".kokoro/coerce_logs.sh",
     ".kokoro/common.cfg",
     ".kokoro/common.sh",