Add serenity-cucumber sample folder

[vishantkkk]

What

Adds a serenity-cucumber/ sample folder alongside the existing java/, junit-4/, junit-5/, and testng/ variants — covers the Serenity-Cucumber BDD framework being added to BrowserStack Load Testing under LTS-2849.

Mirrors the junit-5 structure with two scenarios (add-to-cart, checkout) on bstackdemo.com, expressed as Gherkin features and run via the JUnit 5 Platform Suite + Cucumber JUnit Platform Engine. Uses RemoteWebDriver against a local Selenium Grid hub at localhost:4444/wd/hub, matching the rest of the repo.

Folder contents

serenity-cucumber/
├── README.md                       (verbatim copy of junit-5/README.md, only the cd line changes)
├── browserstack-load.yml           (verbatim copy of junit-5/, framework: serenity-cucumber)
├── pom.xml                         (Selenium 4.15 + Serenity 4.2 + Cucumber 7.20 + JUnit 5)
└── src/test/
    ├── java/com/example/
    │   ├── RunCucumberTest.java    (JUnit 5 Platform Suite runner)
    │   └── StepDefs.java           (RemoteWebDriver + bstackdemo.com flows)
    └── resources/features/
        └── bstackdemo.feature      (2 BDD scenarios)

What differs from sibling variants (and why)

Aspect	Siblings	serenity-cucumber	Reason
maven.compiler.source/target	11	17	Serenity 4.x requires JDK 17+
Surefire <include>	**/*Test.java	**/RunCucumberTest.java	JUnit 5 Platform Suite class must be selected explicitly
Surefire failIfNoTests	not set	true	Cucumber @ignore can skip every scenario; without this, Maven exits 0 on zero work and the load test reports false success
Deps	Selenium + JUnit/TestNG	+ Serenity 4.2 + Cucumber 7.20 + JUnit Platform Suite	BDD requires these
Source files	SimpleTest.java	RunCucumberTest.java + StepDefs.java + bstackdemo.feature	BDD shape: runner + step defs + Gherkin
framework: in YAML	junit / testng	serenity-cucumber	Maps to LT backend constant SELENIUM_FRAMEWORK_SERENITY_CUCUMBER

Verifying locally

# 1. Start a local Selenium Grid hub
docker run -d -p 4444:4444 --shm-size=2g selenium/standalone-chrome:latest

# 2. Compile + run the BDD scenarios
cd serenity-cucumber
mvn test

[vishantkkk]

semgrep/ci