Testing Error inside jenkins

[mint light]

pipeline {
agent any

environment {
    dockerImage = ''
    registry = 'yashkhati/pythonapp'
}

stages {
    stage('Checkout') {
        steps {
            checkout scmGit(branches: [[name: '*/main']], extensions: [], userRemoteConfigs: [[url: 'https://github.com/Yash-codeAndDev/DevOps_PythonApp.git']])
        }
    }

    stage('Build Docker Image') {
        steps {
            script {
                // Build the Docker image from the specified directory
                
                    dockerImage = docker.build registry
                    echo "Docker image built: ${dockerImage.id}"
            }
        }
    }

    stage('Run Tests') {
        steps {
            script {
                docker.image("${dockerImage.id}").inside {
                    sh 'pytest'
                }
            }
        }
    }
    

    // Add more stages as needed, e.g., deployment, testing
}

}

i am getting error on Run Test can anyone tell me why ? Error : Jenkins does not seem to be running inside a container

[queen dome]

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[queen dome]

Please format your code to make it more readable.
For java, it should look like this:
```​​​`​java
public void foo() {

}
​​​`​```

[tiny gyro]

What's the error?

[mint light]

Error : Jenkins does not seem to be running inside a container

[amber helm]

How is that related to java?