fixed directory deletion copy/paste

src/main/java/de/hftstuttgart/dtabackend/utils/JGitUtil.java

@@ -35,7 +35,7 @@ public class JGitUtil {
         {
         	//create companion checkout dir "targetPath"+"_checkout"
             checkoutDirectory = new File(targetPath+"_checkout");
-            if (targetDirectory.exists()) {
+            if (checkoutDirectory.exists()) {
             	LOG.debug("clone checkout directory existing yet, deleting now");
             	FileSystemUtils.deleteRecursively(checkoutDirectory);
             }