GitLab plugin is not working

### Jenkins and plugins versions report

Environment

```text
Paste the output here
```

### What Operating System are you using (both controller, and any agents involved in the problem)?

Jenkins is running on oracle linux 8 into docker container.

### Reproduction steps

Create a new pipeline job. In build triggers section I want to check "Build when a change is pushed to GitLab." but the trigger does not appear. Then in the pipeline section I select "Pipeline script from SCM". Specify the URL of the git repository that I want to. Finally, I set the branch and Jenkinsfile as Script Path and build the job.

### Expected Results

Everytime that I pushed the repository, jenkins will take the jenkinsfile from the repo and execute the scripts.

### Actual Results

It does not work. Everytime that I pushed the repository, jenkins does not detect the pushed from gitlab. I cannot set the gitlab server in the configure system section. I cannot set the trigger "Build when a change is pushed to GitLab.". My automatic integration is failing.

### Anything else?

I tried reinstalling the plugin several times, but it does not work either