Resolve "Move EE-specific tasks to `ee/lib/tasks` directory"

What does this MR do?

› git diff ce/master..origin/master --name-status ./lib/tasks | grep -e '^A' | cut -f2 | xargs -t -L1 -I % dirname % | xargs -t -L1 -I % mkdir -p ee/%                

dirname lib/tasks/geo.rake
mkdir -p ee/lib/tasks
dirname lib/tasks/gitlab/artifacts.rake
dirname lib/tasks/gitlab/elastic.rake
mkdir -p ee/lib/tasks/gitlab
dirname lib/tasks/gitlab/lfs.rake
mkdir -p ee/lib/tasks/gitlab
dirname lib/tasks/migrate/ldap.rake
mkdir -p ee/lib/tasks/gitlab
mkdir -p ee/lib/tasks/migrate

and then

› git diff ce/master..origin/master --name-status ./lib/tasks | grep -e '^A' | cut -f2 | xargs -t -L1 -I % git mv % ee/%               

git mv lib/tasks/geo.rake ee/lib/tasks/geo.rake
git mv lib/tasks/gitlab/artifacts.rake ee/lib/tasks/gitlab/artifacts.rake
git mv lib/tasks/gitlab/elastic.rake ee/lib/tasks/gitlab/elastic.rake
git mv lib/tasks/gitlab/lfs.rake ee/lib/tasks/gitlab/lfs.rake
git mv lib/tasks/migrate/ldap.rake ee/lib/tasks/migrate/ldap.rake

Does this MR meet the acceptance criteria?

• Review
  • Has been reviewed by Backend
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together
• Internationalization required/considered
• If paid feature, have we considered GitLab.com plan and how it works for groups and is there a design for promoting it to users who aren't on the correct plan

What are the relevant issue numbers?

Closes #4637 (closed)