修复 Cleanroom 本地安装完成后会删除安装器的问题 (#5257)

HMCLCore/src/main/java/org/jackhuang/hmcl/download/cleanroom/CleanroomInstallTask.java

@@ -92,7 +92,10 @@ public final class CleanroomInstallTask extends Task<Version> {
 
     @Override
     public void postExecute() throws Exception {
+        if (remote != null) {
             Files.deleteIfExists(installer);
+        }
+
         setResult(task.getResult());
     }