Add a Breach and Attack Simulation CI template

What does this MR do and why?

Introduce a Security/BAS.latest.gitlab-ci.yml CI template to enable adoption of the BAS incubation project's extended DAST configuration and establish reference configuration for using the callback service container.

Close #410071 (closed).

How to set up and validate locally

1. Create a new project in GitLab with the contents below.
2. Verify two jobs run which run DAST against the example vulnerable web app.
3. Both jobs include vulnerabilities for CWE-94 with a severity of CRITICAL.
4. See dast-callback-attacks demo for an example.

include:
  - remote: https://gitlab.com/gitlab-org/gitlab/-/raw/410071-add-bas-ci-template/lib/gitlab/ci/templates/Security/BAS.latest.gitlab-ci.yml

stages:
  - dast

variables:
  DAST_BROWSER_INCLUDE_ONLY_RULES: "94.4.2,611.1"
  DAST_WEBSITE: "http://vulnapp"
  VULNAPP_IMAGE: registry.gitlab.com/gitlab-org/incubation-engineering/breach-and-attack-simulation/security-products/vulnerable-web-apps/node:latest

dast:
  extends: .dast_with_bas_using_services
  services:
    - name: "$SECURE_ANALYZERS_PREFIX/callback:$BAS_CALLBACK_IMAGE_TAG"
      alias: callback
    - name: $VULNAPP_IMAGE
      alias: vulnapp

dast_with_bas:
  extends:
    - dast
    - .dast_with_bas_using_services
  services:
    - name: "$SECURE_ANALYZERS_PREFIX/callback:$BAS_CALLBACK_IMAGE_TAG"
      alias: callback
    - name: $VULNAPP_IMAGE
      alias: vulnapp

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #410071 (closed)