hack/update-ubuntu-image.sh: add --flavor <flavor> flag

Signed-off-by: Norio Nomura <[email protected]>

Author: norio-nomura

hack/update-ubuntu-image.sh

@@ -5,7 +5,7 @@ function print_help() {
 $(basename "${BASH_SOURCE[0]}"): Update the Ubuntu image location in the specified templates
 
 Usage:
-  $(basename "${BASH_SOURCE[0]}") [--minimal|--server] [--version <version>] <template.yaml>...
+  $(basename "${BASH_SOURCE[0]}") [--flavor <flavor>|--minimal|--server] [--version <version>] <template.yaml>...
 
 Description:
   This script updates the Ubuntu image location in the specified templates.
@@ -32,8 +32,9 @@ Examples:
   $ $(basename "${BASH_SOURCE[0]}") --minimal --version 24.04 ~/.lima/docker/lima.yaml
 
 Flags:
-  --server             Use the server flavor image
-  --minimal            Use the minimal flavor image
+  --flavor <flavor>    Use the specified flavor image
+  --server             Shortcut for --flavor server
+  --minimal            Shortcut for --flavor minimal
   --version <version>  Use the specified version
   -h, --help           Print this help message
 HELP
@@ -186,6 +187,16 @@ while [[ $# -gt 0 ]]; do
 		print_help
 		exit 0
 		;;
+	--flavor)
+		if [[ -n $2 && $2 != -* ]]; then
+			flavor="$2"
+			shift
+		else
+			echo "Error: --flavor requires a value" >&2
+			exit 1
+		fi
+		;;
+	--flavor=*) flavor="${1#*=}" ;;
 	--minimal) flavor="minimal" ;;
 	--server) flavor="server" ;;
 	--version)