[Security Solution] Unskip Related Integrations Cypress test (elastic#239532)

**Resolves: elastic#239356

🟢 Flaky test runner:
https://buildkite.com/elastic/kibana-flaky-test-suite-runner/builds/9560

# Summary
This PR unskips the Related Integrations Cypress tests. The tests were
previously failing because one of the Fleet packages they depend on
contained a YAML syntax error. That issue has now been fixed
([PR](elastic/integrations#15669)), so the tests
can be safely re-enabled.

The diff appears large, but the only functional change is the removal of
`.only`. The rest comes from Prettier formatting.

Author: nikitaindik