fix: fixed linting and license headers

tools/target-server-validator/test/create_notification_channel.sh

@@ -1,4 +1,18 @@
-#!/bin/bash
+#!/bin/sh
+
+# Copyright 2024 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
 
 JSON_FILE="./test/email-channel.json"
 PROJECT_ID=$1
@@ -7,15 +21,16 @@ type=$(jq -r '.type' $JSON_FILE)
 displayName=$(jq -r '.displayName' $JSON_FILE)
 emailAddress=$(jq -r '.labels.email_address' $JSON_FILE)
 
-list_response=$(gcloud alpha monitoring channels list --filter="type='$type' AND displayName=\"$displayName\" AND labels.email_address='$emailAddress'" --format=json --verbosity=none --project=$PROJECT_ID --format=json 2>&1)
+list_response=$(gcloud alpha monitoring channels list --filter="type='$type' AND displayName=\"$displayName\" AND labels.email_address='$emailAddress'" --format=json --verbosity=none --project="$PROJECT_ID" --format=json 2>&1)
 
-if [[ $list_response == "[]" ]]; then
+if [ "$list_response" = "[]" ]; then
 
     # create if not existing
     create_response=$(gcloud beta monitoring channels create --channel-content-from-file="$JSON_FILE" --project="$PROJECT_ID" 2>&1)
-
-    if [ $? -eq 0 ]; then
-        channel_id=$(echo "$create_response" | grep -oE "projects/"$PROJECT_ID"/notificationChannels/[0-9]+" | awk -F'/' '{print $4}')
+    exit_status=$?
+
+    if [ "$exit_status" -eq 0 ]; then
+        channel_id=$(echo "$create_response" | grep -oE "projects/$PROJECT_ID/notificationChannels/[0-9]+" | awk -F'/' '{print $4}')
         echo "$channel_id"
     else
         echo