Fix test environment pollution in spec/lib/gitlab/request_context_spec.rb

Closes #58969

See merge request gitlab-org/gitlab-ce!26167

(cherry picked from commit ef9b6012)

fcf418d6 Fix test environment pollution in spec/lib/gitlab/request_context_spec.rb

Fix health checks not working behind load balancers

Closes #58573

See merge request gitlab-org/gitlab-ce!26055

(cherry picked from commit ef19ded4)

01203e71 Fix health checks not working behind load balancers

As mentioned in
https://gitlab.com/gitlab-org/gitlab-ee/issues/9035#note_129093444,
Rails 5 switched ActionDispatch::Request so that it no longer inherits
Rack::Request directly. A middleware that uses Rack::Request to
read the environment may see stale request parameters if
another middleware modifies the environment via ActionDispatch::Request.
To be safe, we should be using ActionDispatch::Request everywhere.

Signed-off-by: Rémy Coutable <remy@rymai.me>

Remove superfluous lib: true, type: redis, service: true, models: true, services: true, no_db: true, api: true

Signed-off-by: Rémy Coutable <remy@rymai.me>

 - cleanup formating in haml
 - clarify time window is in seconds
 - cleanup straneous chunks in db/schema
 - rename count_uniqe_ips to update_and_return_ips_count
 - other