Convert scripts/verify-tff-mapping into a spec

What does this MR do and why?

This MR converts scripts/verify-tff-mapping into spec/tooling/tests_yml_spec.rb. It also remove the now unnecessary verify-tests-yml CI job.

Follow-up of !119340 (comment 1375414456).

How to set up and validate locally

tff -f tests.yml tests.yml

bin/rspec $(tff -f tests.yml tests.yml)

Verify that all checks were converted properly

# Before
git checkout master
rg -o -r '$1'  "^\s*source: (.*)" scripts/verify-tff-mapping > before

# After
git checkout pl-tests-yml-spec
rg -o -r '$1'  "^\s*source: (.*)" spec/tooling/tests_yml_spec.rb > after

# Diff
diff -u before after
# no output - MATCHES

List

'ee/app/controllers/admin/licenses_controller.rb',
'app/finders/admin/projects_finder.rb',
'ee/app/finders/ee/projects_finder.rb',
'ee/lib/world.rb',
'lib/gitaly/server.rb',
'lib/gitlab/usage_data_counters/foo.rb',
'lib/gitlab/ci/config/base.rb',
'ee/lib/gitlab/ci/config/base.rb',
'tooling/danger/specs/project_factory_suggestion.rb',
'config/initializers/action_mailer_hooks.rb',
'db/structure.sql',
'db/migrate/20221014034338_populate_releases_access_level_from_repository.rb',
'db/post_migrate/20230105172120_sync_new_amount_used_with_amount_used_on_ci_namespace_monthly_usages_table.rb',
'app/views/admin/dashboard/index.html.haml',
'ee/app/views/subscriptions/new.html.haml',
'spec/models/issue_spec.rb',
'ee/spec/models/ee/user_spec.rb',
'ee/spec/services/ee/notification_service_spec.rb',
'spec/factories/users.rb',
'ee/spec/factories/users.rb',
'data/whats_new/202101140001_13_08.yml',
'doc/index.md',
'app/workers/new_worker.rb',
'ee/app/workers/new_worker.rb',
'lib/gitlab/usage_data_counters/known_events/common.yml',
'app/mailers/previews/foo.rb',
'ee/app/mailers/previews/foo.rb',
'ee/app/mailers/previews/license_mailer_preview.rb',
'glfm_specification/foo',
'ee/config/metrics/counts_all/20221114065035_delete_merge_request.yml',
'ee/lib/ee/gitlab/usage_data_counters/known_events/common.yml',
'config/feature_categories.yml',
'vendor/project_templates/gitbook.tar.gz',

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.