fix(ci): fix release script (#10325)

Author: huangjw806

ci/scripts/release.sh

@@ -40,7 +40,7 @@ curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip
 unzip -q awscliv2.zip && ./aws/install && mv /usr/local/bin/aws /bin/aws
 
 echo "--- Update risingwave release version"
-if [[ -n "${BUILDKITE_TAG+x}" ]]; then
+if [[ -n "${BUILDKITE_TAG}" ]]; then
   toml set --toml-path Cargo.toml workspace.package.version ${BUILDKITE_TAG#*v}
 fi
 
@@ -58,7 +58,7 @@ elif [[ -n "${BINARY_NAME+x}" ]]; then
     aws s3 cp risingwave-${BINARY_NAME}-x86_64-unknown-linux.tar.gz s3://risingwave-nightly-pre-built-binary
 fi
 
-if [[ -n "${BUILDKITE_TAG+x}" ]]; then
+if [[ -n "${BUILDKITE_TAG}" ]]; then
   echo "--- Install gh cli"
   yum install -y dnf
   dnf install -y 'dnf-command(config-manager)'