A runner installed on a cluster will now use the
cluster's `cluster_type` as its `runner_type`.

- This is to avoid colision with EE ClusterUpdateAppWorker

- Creates new route
- Creates new controller action
- Creates call stack:
  Clusterss::ApplciationsController calls -->
  Clusters::Applications::UpdateService calls -->
  Clusters::Applications::ScheduleUpdateService calls -->
  ClusterUpdateAppWorker calls -->
  Clusters::Applications::PatchService -->
  ClusterWaitForAppInstallationWorker

DRY req params

Adds gcp_cluster:cluster_update_app queue

Schedule_update_service is uneeded

Extract common logic to a parent class (UpdateService will need it)

Introduce new UpdateService

Fix rescue class namespace

Fix RuboCop offenses

Adds BaseService for create and update services

Remove request_handler code duplication

Fixes update command

Move update_command to ApplicationCore so all apps can use it

Adds tests for Knative update_command

Adds specs for PatchService

Raise error if update receives an unistalled app

Adds update_service spec

Fix RuboCop offense

Use subject in favor of go

Adds update endpoint specs for project namespace

Adds update endpoint specs for group namespace

- deletes schedule_installation_service.rb
- moves schedule_installation_service.rb logic to create_service.rb
- moves specs as well

Removes code duplication

Remove unecessary spec block

Abide review suggestions

Test installable applications which are not associated to a cluster

Fix a typo

Removes duplciated expectation

Reuse variable instead of redefining

Remove method in favor of a local scoped lambda

Improve 'failing service' shared examples

Test the increase of status count

Remove duplicated test

Enable fronzen literal

Many changes were also made to tests that expected this to default to
false.

Ability to override Issuer Email for Cert Manager

See merge request gitlab-org/gitlab-ce!23503