Fixed jenkins file

Jenkinsfile

@@ -1,8 +1,5 @@
 pipeline {
     agent any 
-    stages {
-		stage('Preparation') { 
-			properties([
 	parameters([
 	 string(
 		defaultValue: '0',
@@ -22,8 +19,7 @@ pipeline {
 		 name: 'KAGGLE_KEY'
 	 )
 	])
-			 ])
-		}
+    stages {
         stage('checkout') {
             steps {
                 checkout([$class: 'GitSCM', branches: [[name: '*/master']], doGenerateSubmoduleConfigurations: false, extensions: [], submoduleCfg: [], userRemoteConfigs: [[url: 'https://git.wmi.amu.edu.pl/s426206/ium_426206.git']]])
@@ -42,8 +38,10 @@ pipeline {
         }
 		
 		stage('end') {
+            steps {
 				//Zarchiwizuj wynik
 				archiveArtifacts 'output.txt'
 			}
 		}
+    }
 }