Bump io.cucumber:cucumber-bom from 7.18.1 to 7.21.0 in /examples

Bumps [io.cucumber:cucumber-bom](https://github.com/cucumber/cucumber-jvm) from 7.18.1 to 7.21.0.
- [Release notes](https://github.com/cucumber/cucumber-jvm/releases)
- [Changelog](https://github.com/cucumber/cucumber-jvm/blob/main/CHANGELOG.md)
- [Commits](cucumber/cucumber-jvm@v7.18.1...v7.21.0)

---
updated-dependencies:
- dependency-name: io.cucumber:cucumber-bom
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

examples/cucumber/build.gradle

@@ -12,7 +12,7 @@ dependencies {
     implementation 'org.seleniumhq.selenium:selenium-firefox-driver'
     implementation 'org.seleniumhq.selenium:selenium-chrome-driver'
 
-    testImplementation platform('io.cucumber:cucumber-bom:7.18.1')
+    testImplementation platform('io.cucumber:cucumber-bom:7.21.0')
     testImplementation 'io.cucumber:cucumber-java'
     testImplementation 'io.cucumber:cucumber-junit'
     testImplementation 'org.testcontainers:selenium'