chore: add help section for the driver download script (#196)

scripts/download_driver_for_all_platforms.sh

@@ -6,12 +6,26 @@ set +x
 trap "cd $(pwd -P)" EXIT
 cd "$(dirname $0)"
 
+if [[ ($1 == '-h') || ($1 == '--help') ]]; then
+  echo ""
+  echo "This script for downloading playwright-cli binaries for all platforms."
+  echo "The downloaded files will be put into directory 'driver-bundle/src/main/resources/driver'."
+  echo ""
+  echo "Usage: scripts/download_driver_for_all_platforms.sh [option]"
+  echo ""
+  echo "Options:"
+  echo "  -h, --help     display help information"
+  echo "  -f, --force    delete existing drivers and download them again"
+  echo ""
+  exit 0
+fi
+
 CLI_VERSION=$(head -1 ./CLI_VERSION)
 FILE_PREFIX=playwright-cli-$CLI_VERSION
 
 cd ../driver-bundle/src/main/resources
 
-if [[ $1 == '-f' ]]; then
+if [[ ($1 == '-f') || ($1 == '--force') ]]; then
   echo "Deleting existing drivers from $(pwd)"
   rm -rf driver
 fi
@@ -43,3 +57,7 @@ do
   cd -
 done
 
+echo ""
+echo "All drivers have been downloaded successfully, use '-f' or '--force' option to delete and download them again if you want."
+echo "For more details, you can use '-h' or '--help' option, or read the CONTRIBUTING.md for reference."
+echo ""