Removes Airborne from E2E tests

What does this MR do and why?

• Removes the usage of airborne from the Geo E2E API tests.
• Fix Rubocop infractions in the Geo spec (mostly replacing instance variables with let)
• Removes the airborne dependency

This is to prevent confusion over whether to use airborne or Support::API. When we have both and we aren't explicit, it can lead to issues when the wrong module is invoked. e.g:

1. #431317 (closed)
2. !96991 (merged)
3. !30793 (merged)

Resolves gitlab-org/quality/quality-engineering/team-tasks#1115 (closed)

Passing test results

Note, the Geo tests don't run in MRs or in staging. To test I had to execute locally against staging-ref;

Running locally

This updates a number of orchestrated tests so it is probably more efficient to look at pipeline results.

To run locally against staging-ref apply the following patch (we can skip setup as Geo is already configured on staging-ref):

diff --git a/qa/qa/ee/scenario/test/geo.rb b/qa/qa/ee/scenario/test/geo.rb
index 695ed72d8176..6c57011708d7 100644
--- a/qa/qa/ee/scenario/test/geo.rb
+++ b/qa/qa/ee/scenario/test/geo.rb
@@ -25,21 +25,7 @@ def perform(options, *rspec_options)
             QA::Support::GitlabAddress.define_gitlab_address_attribute!(QA::Runtime::Scenario.geo_primary_address)
             QA::Runtime::Scenario.define(:network, 'geo')
 
-            unless options[:geo_skip_setup?]
-              Geo::Primary.act do
-                add_license
-                set_replication_password
-                set_primary_node
-                add_secondary_node
-              end
 
-              Geo::Secondary.act do
-                replicate_database
-                reconfigure
-                wait_for_services
-                authorize
-              end
-            end
 
             # Save the scenario class name
             QA::Runtime::Scenario.define(:klass, self.class.name)
diff --git a/qa/qa/runtime/address.rb b/qa/qa/runtime/address.rb
index c622051bb6da..e76ae7ebd25e 100644
--- a/qa/qa/runtime/address.rb
+++ b/qa/qa/runtime/address.rb
@@ -12,7 +12,13 @@ def initialize(instance, page)
 
       def host
         if @instance.is_a?(Symbol)
-          Runtime::Scenario.send("#{@instance}_address")
+          if @instance == :geo_primary
+            "https://staging-ref.gitlab.com"
+          elsif @instance == :geo_secondary
+            "https://geo.staging-ref.gitlab.com"
+          else
+            Runtime::Scenario.send("#{@instance}_address")
+          end
         else
           @instance.to_s
         end

Run the test:

GEO_STAGING_REF_URL="https://geo.staging-ref.gitlab.com" GITLAB_QA_ACCESS_TOKEN=1P QA_LOG_LEVEL=DEBUG QA_GITLAB_URL=https://staging-ref.gitlab.com GITLAB_ADMIN_USERNAME=gitlab-qa-admin GITLAB_ADMIN_PASSWORD=1P bundle exec rspec qa/specs/features/ee/api/12_systems/geo/geo_nodes_spec.rb