Updates security templates to mention edge cases

* Renames 'Security Release' template to 'Security Release Tracking
  Issue'
* Remove unnecessary section from the Security Release Tracking Issue
  (such as QA)
* Add an item to the 'Security Developer Workflow' to specify issues
  with less than 4 MR associated need to be notified to Release Managers

.gitlab/issue_templates/Security Release.md → .gitlab/issue_templates/Security Release Tracking Issue.md

@@ -8,12 +8,6 @@ Set the title to: `Security Release: 12.2.X, 12.1.X, and 12.0.X`
 
 -------
 
-## Releases tasks
-
-- https://gitlab.com/gitlab-org/release/docs/blob/master/general/security/release-manager.md
-- https://gitlab.com/gitlab-org/release/docs/blob/master/general/security/developer.md
-- https://gitlab.com/gitlab-org/release/docs/blob/master/general/security/security-engineer.md
-
 ## Version issues:
 
 12.2.X, 12.1.X, 12.0.X: {release task link}
@@ -25,12 +19,9 @@ your security issues as related to this release tracking issue. You can do this
 in the "Linked issues" section below this issue description.
 
 :warning: If your security issues are not marked as related to this release
-tracking issue, their merge requests may not be included in the security
+tracking issue, their merge requests will not be included in the security
 release.
 
-## QA
-{QA issue link}
-
 ## Blog post
 
 Dev: {https://dev.gitlab.org/gitlab/www-gitlab-com/merge_requests/ link}<br/>

.gitlab/issue_templates/Security developer workflow.md

@@ -28,8 +28,8 @@ After your merge request has been approved according to our [approval guidelines
    * You can use the script `bin/secpick` instead of the following steps, to help you cherry-picking. See the [secpick documentation]
 - [ ] Create each MR targeting the stable branch `X-Y-stable`, using the [Security Release merge request template].
    * Every merge request will have its own set of TODOs, so make sure to complete those.
-- [ ] On the "Related merge requests" section, ensure all MRs are linked to this issue.
-   * This section should only list the merge requests created for this issue: One targeting `master` and the 3 backports.
+- [ ] On the "Related merge requests" section, ensure that `4` merge requests are associated: The one targeting `master` and the `3` backports.
+- [ ] If this issue requires less than `4` merge requests, post a message on the Security Release Tracking Issue and ping the Release Managers.
 
 ## Documentation and final details