Revert "Tee output so we can see it in journald logs (#346)" for dataproc (#354)

This partially reverts commit 9bd46a1.

Root Cause:
1. The exec > >(tee -a "${POST_STARTUP_OUTPUT_FILE}") creates a tee
subprocess that remains alive
2. The background process that waits for Jupyter inherits file
descriptors from tee
3. When the main startup script exits, tee subprocess stays alive
because the background process still has the pipes open
4. google-startup-scripts.service remains stuck in "activating" state
indefinitely, waiting for all child processes
5. google-dataproc-agent.service has
After=google-startup-scripts.service, so it never starts
6. This creates a race condition where the background Jupyter
configuration runs while Dataproc is still writing its config

Symptoms:
- google-startup-scripts.service stuck in "activating" for hours
  - google-dataproc-agent.service never starts (ConditionResult=no)

Author: june-hua

startupscript/dataproc/startup.sh

@@ -149,11 +149,11 @@ readonly GIT_IGNORE="${USER_HOME_DIR}/gitignore_global"
 cd /tmp || exit
 
 # Send stdout and stderr from this script to a file for debugging.
-# Use tee to also send output to journald logs.
 # Make the .wb directory as the user so that they own it and have correct linux permissions.
 ${RUN_AS_LOGIN_USER} "mkdir -p '${USER_WORKBENCH_CONFIG_DIR}'"
 ${RUN_AS_LOGIN_USER} "ln -sf '${USER_WORKBENCH_CONFIG_DIR}' '${USER_WORKBENCH_LEGACY_CONFIG_DIR}'"
-exec > >(tee -a "${POST_STARTUP_OUTPUT_FILE}") 2>&1
+exec >> "${POST_STARTUP_OUTPUT_FILE}"
+exec 2>&1
 
 #######################################
 # Emit a message with a timestamp
@@ -917,8 +917,8 @@ cat << EOF >"${WORKBENCH_BOOT_SCRIPT}"
 # This script is run on instance boot to configure the instance for Workbench.
 
 # Send stdout and stderr from this script to a file for debugging.
-# Use tee to also send output to journald logs.
-exec > >(tee -a "${WORKBENCH_BOOT_SERVICE_OUTPUT_FILE}") 2>&1
+exec >> "${WORKBENCH_BOOT_SERVICE_OUTPUT_FILE}"
+exec 2>&1
 
 # Pick up environment from the ~/.bashrc
 source "${USER_BASHRC}"