Removing unused var

Author: JoeColeman95

packer/linux/conf/bin/bk-install-elastic-stack.sh

@@ -135,8 +135,6 @@ set_always         "BUILDKITE_AGENTS_PER_INSTANCE" "$BUILDKITE_AGENTS_PER_INSTAN
 # also set via /etc/systemd/system/buildkite-agent.service.d/environment.conf
 set_always         "BUILDKITE_TERMINATE_INSTANCE_AFTER_JOB" "$BUILDKITE_TERMINATE_INSTANCE_AFTER_JOB"
 set_always         "BUILDKITE_TERMINATE_INSTANCE_ON_DISK_FULL" "$BUILDKITE_TERMINATE_INSTANCE_ON_DISK_FULL"
-
-set_always         "BUILDKITE_AGENT_BUILD_PATH" "$BUILDKITE_AGENT_BUILD_PATH"
 set_always         "BUILDKITE_PURGE_BUILDS_ON_DISK_FULL" "$BUILDKITE_PURGE_BUILDS_ON_DISK_FULL"
 set_always         "BUILDKITE_ECR_POLICY" "${BUILDKITE_ECR_POLICY:-none}"
 set_always         "BUILDKITE_SECRETS_BUCKET" "$BUILDKITE_SECRETS_BUCKET"