chore: remove staging bucket v2 (#726)

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Source-Link: googleapis/synthtool@572ef8f

.kokoro/release/publish_javadoc.sh

@@ -24,11 +24,6 @@ if [[ -z "${STAGING_BUCKET}" ]]; then
   exit 1
 fi
 
-if [[ -z "${STAGING_BUCKET_V2}" ]]; then
-  echo "Need to set STAGING_BUCKET_V2 environment variable"
-  exit 1
-fi
-
 # work from the git root directory
 pushd $(dirname "$0")/../../
 

synth.metadata

@@ -11,7 +11,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-bigquerydatatransfer.git",
-        "sha": "a6c4e691788d217c2c744170d58e89b130da7afe"
+        "sha": "0f890ec54b69be6f8353ef86528ddfd0cd671c06"
       }
     },
     {
@@ -26,7 +26,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "0b064d767537e0675fc053e53fca473c5c701fb8"
+        "sha": "572ef8f70edd9041f5bcfa71511aed6aecfc2098"
       }
     }
   ],