Remove ref to securityheaders

See OWASP/www-project-secure-headers#193

tests_suite.yml

@@ -2,7 +2,6 @@ name: HTTP security response headers test suites
 vars:
   target_site: ''
   logout_url: ''
-  internet_facing: false
   request_timeout_in_seconds: 20
 testcases:
   - name: Strict-Transport-Security
@@ -191,16 +190,3 @@ testcases:
         assertions:
           - result.statuscode ShouldEqual 200
           - result.headers.X-XSS-Protection ShouldBeNil
-  - name: SecurityHeaders-Rating
-    skip:
-      - internet_facing ShouldEqual true
-    steps:
-      - type: http
-        method: GET
-        url: >-
-          https://securityheaders.com/?q={{.target_site}}&hide=on&followRedirects=on
-        skip_body: false
-        timeout: '{{.request_timeout_in_seconds}}'
-        assertions:
-          - result.statuscode ShouldEqual 200
-          - result.body ShouldContainSubstring '<div class="score_lightgreen"><span>A+</span></div>'