terraform-eventbridge-scheduled-lambda: Update runtime to python3.12

Author: kakakakakku

terraform-eventbridge-scheduled-lambda/main.tf

@@ -43,7 +43,7 @@ module "lambda_function" {
   function_name = "${random_pet.this.id}-lambda"
   description   = "My awesome lambda function"
   handler       = "index.lambda_handler"
-  runtime       = "python3.8"
+  runtime       = "python3.12"
   publish       = true
 
   source_path = "${path.module}/../terraform-fixtures/python"