Remove `License-Management.gitlab-ci.yml` completely
This is a follow-up from https://gitlab.com/gitlab-org/gitlab/-/issues/213572
In %"13.0" we dropped support for `License-Management` CI template. We've updated it to show users an error message with how to update their config for `License-Scanning`. Now we need just to delete the file completely.
## Testing
Regression tests on the Secure Test projects should capture Licence Scanning testing.
## Timing
The work should occur in 13.11 but not apply until as close to 14.0 as possible - aka remove this as close to the end of 13.11 as possible please but not missing the cutoff
## Release Post
this MUST be announced in 13.9-14.0 per policy
* [x] 13.9
* [x] 13.10
* [ ] 13.11 [MR](https://gitlab.com/gitlab-com/www-gitlab-com/-/merge_requests/77409)
* [ ] 13.12 [MR](https://gitlab.com/gitlab-com/www-gitlab-com/-/merge_requests/78888)
* [ ] 14.0 [MR](https://gitlab.com/gitlab-com/www-gitlab-com/-/merge_requests/77410)
## Changelog
* [ ] This MUST be announced in 14.0 changelog
## Blog post
* [x] [unfiltered blog post](https://about.gitlab.com/blog/2021/02/08/composition-analysis-14-deprecations-and-removals/)
issue