Can't copy test result file from the top layer of docker container to local or any visible contaner for pulishing via HTML Publicher - docker

Question

I run my regression tests on docker container and I am trying to publish Test Results in jenkins-pipline using HTML-Publisher. This doesn't work properly, thought I get a mistake by trying to copy the result-file from docker container (Error type: such file does not exist).
My Jenkinsfile looks like this:
//https://www.jenkins.io/doc/book/pipeline/syntax/
pipeline {
agent any
stages {
stage('Deploy webstore') {
steps {
//start and run an application container using .yml file
sh "docker compose -f webstore-compose.yml up -d"
}
}
stage ('Regression Tests') {
//setting up docker container for regression tests
agent {
docker {
image 'localhost:5000/dotnet_s3'
args '--add-host=host.docker.internal:host-gateway'
reuseNode true
}
}
steps {
//running tests located in /guiautomationtask directory in the top layer and logging into testResults.html file
sh 'id; cd /guiautomationtask; dotnet test --logger "html;logfilename=testResults.html"'
sleep(time: 10, unit: "SECONDS")
/*To Do:
copy logfile from container to local*/
//console output
echo "++++++++++++++++++++++++++++++++++ Display Test Results in the Console +++++++++++++++++++++++++++++++++++++++++"
echo "Running build ${env.BUILD_ID} on jenkins ${env.JENKINS_URL}"
echo "current docker container ID is ${hostname}"
sh "id; cd /guiautomationtask; dotnet test -v normal"
echo "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++"
/*sh "dotnet publish /guiautomationtask/GuiTest/GuiTest.csproj"
sleep(time: 10, unit: "SECONDS")*/
}
}
stage ('Publish results') {
steps {
//view test-logs via HTML Publisher plugin
publishHTML(target:[
allowMissing: false,
alwaysLinkToLastBuild: true,
keepAll: false,
reportDir: "", //here should be report directory with saved html report file
reportFiles: "testResults.html",
reportName: 'HTML-Report',
//reportTitles: ''
])
echo "artifacts saved in zip";
}
}
}
post {
always {
//stop an application container
sh "docker compose -f webstore-compose.yml stop"
}
}
}