Draft: Add new RuboCop rule `RSpec/AggregateExamples` of test-prof

What does this MR do and why?

This MR introduces a new 👮 rule RSpec/AggregateExamples.

See https://test-prof.evilmartians.io/#/misc/rubocop?id=rspecaggregateexamples:

This cop encourages you to use one of the greatest features of the recent RSpec - aggregating failures within an example.

Draft?

TODO The question is why? Show-case some examples where apply this 👮 helped to reduce the runtime.

Screenshots or screen recordings

Top 50 offenders:

$ be rubocop -f worst --only RSpec/AggregateExamples --parallel

555   spec/lib/gitlab/regex_spec.rb
272   spec/features/security/project/internal_access_spec.rb
271   spec/features/security/project/public_access_spec.rb
248   spec/features/security/project/private_access_spec.rb
205   spec/models/application_setting_spec.rb
196   spec/models/packages/package_spec.rb
183   spec/models/project_spec.rb
158   spec/models/member_spec.rb
140   spec/models/user_spec.rb
115   ee/spec/models/application_setting_spec.rb
86    spec/policies/project_policy_spec.rb
72    spec/lib/gitlab/git/blob_spec.rb
71    spec/lib/gitlab/path_regex_spec.rb
66    ee/spec/policies/group_policy_spec.rb
64    spec/features/security/project/snippet/public_access_spec.rb
61    ee/spec/lib/gitlab/ci/parsers/license_compliance/license_scanning_spec.rb
60    ee/spec/policies/project_policy_spec.rb
56    spec/models/group_spec.rb
48    ee/spec/models/ee/vulnerability_spec.rb
48    spec/features/security/group/private_access_spec.rb
48    spec/features/security/project/snippet/internal_access_spec.rb
46    spec/models/ci/pipeline_spec.rb
42    ee/spec/models/project_spec.rb
40    spec/features/security/group/internal_access_spec.rb
40    spec/features/security/group/public_access_spec.rb
38    ee/spec/models/vulnerabilities/finding_spec.rb
38    spec/lib/gitlab/import_export/project/tree_restorer_spec.rb
37    spec/models/ci/build_spec.rb
37    spec/models/clusters/cluster_spec.rb
37    spec/models/hooks/web_hook_spec.rb
37    spec/models/namespace_spec.rb
35    spec/lib/gitlab/ci/status/build/factory_spec.rb
34    spec/lib/gitlab/ci/config/entry/rules/rule_spec.rb
31    spec/models/issue_spec.rb
30    ee/spec/models/ee/group_spec.rb
30    spec/mailers/emails/profile_spec.rb
29    spec/lib/gitlab/regex_requires_app_spec.rb
28    spec/models/merge_request_spec.rb
26    ee/spec/lib/gitlab/pagination_delegate_spec.rb
25    spec/lib/gitlab/git/tree_spec.rb
25    spec/models/packages/conan/metadatum_spec.rb
23    spec/lib/gitlab/git/commit_spec.rb
22    spec/graphql/types/project_type_spec.rb
22    spec/models/integrations/datadog_spec.rb
22    spec/support/shared_examples/models/packages/debian/distribution_shared_examples.rb
21    ee/spec/features/security/project/internal_access_spec.rb
21    ee/spec/features/security/project/private_access_spec.rb
21    ee/spec/features/security/project/public_access_spec.rb
21    ee/spec/models/epic_spec.rb

How to set up and validate locally

bin/rake rubocop:todo:generate[RSpec/AggregateExamples]

bundle exec rubocop --auto-correct --only RSpec/AggregateExamples spec/features/security/project/internal_access_spec.rb

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.