Execute `exit 1` when shell script `cd` fails

It's dangerous when `cd` fails but following commands keeps running
which would lead to expected results.

For those shell scripts without `set -e`, use `exit 1` before furthur
refactor could be a safe and efficient workaround, for thoes shell
scripts with `-e`, the shell(script) will exit immediately if any
command has a non-zero exit status, so they don't need `exit 1`

Reference:
- https://github.com/koalaman/shellcheck/wiki/SC2164

bin/background_jobs

 #!/usr/bin/env bash
 
-cd $(dirname $0)/..
+cd $(dirname $0)/.. || exit 1
 
 if [ -n "$SIDEKIQ_WORKERS" ] ; then
   exec bin/background_jobs_sk_cluster "$@"

bin/mail_room

 #!/bin/sh
 
-cd $(dirname $0)/..
+cd $(dirname $0)/.. || exit 1
 app_root=$(pwd)
 
 mail_room_pidfile="$app_root/tmp/pids/mail_room.pid"

bin/web_unicorn

 #!/bin/sh
 
-cd $(dirname $0)/..
+cd $(dirname $0)/.. || exit 1
 app_root=$(pwd)
 
 unicorn_pidfile="$app_root/tmp/pids/unicorn.pid"

changelogs/unreleased/ImproveShellScriptsChangeDirException.yml

+---
+title: Execute `exit 1` when shell script `cd` fails
+merge_request: 46122
+author: Peter Dave Hello
+type: other

scripts/lint-doc.sh

 #!/usr/bin/env bash
 
-cd "$(dirname "$0")/.."
+cd "$(dirname "$0")/.." || exit 1
 echo "=> Linting documents at path $(pwd) as $(whoami)..."
 echo
 ERRORCODE=0