Remove FDW enabled check

Since Gitlab 13.2 we don't rely on FDW

ee/lib/system_check/geo/fdw_enabled_check.rb

-# frozen_string_literal: true
-
-module SystemCheck
-  module Geo
-    class FdwEnabledCheck < SystemCheck::BaseCheck
-      set_name 'GitLab Geo tracking database is configured to use Foreign Data Wrapper?'
-      set_skip_reason 'not a secondary node'
-
-      def skip?
-        !Gitlab::Geo.secondary?
-      end
-
-      def check?
-        Gitlab::Geo::Fdw.enabled?
-      end
-
-      def show_error
-        try_fixing_it(
-          'Follow Geo setup instructions to configure secondary nodes with FDW support',
-          'If you upgraded recently check for any new step required to enable FDW'
-        )
-
-        for_more_information('doc/gitlab-geo/database.md')
-      end
-    end
-  end
-end

ee/lib/system_check/rake_task/geo_task.rb

@@ -36,7 +36,6 @@ module SystemCheck
           SystemCheck::Geo::GeoDatabaseConfiguredCheck,
           SystemCheck::Geo::DatabaseReplicationEnabledCheck,
           SystemCheck::Geo::DatabaseReplicationWorkingCheck,
-          SystemCheck::Geo::FdwEnabledCheck,
           SystemCheck::Geo::HttpConnectionCheck
         ] + common_checks
       end

ee/spec/lib/system_check/geo/fdw_enabled_check_spec.rb

-# frozen_string_literal: true
-
-require 'spec_helper'
-require 'rake_helper'
-
-RSpec.describe SystemCheck::Geo::FdwEnabledCheck, :geo do
-  describe '#skip?' do
-    subject { described_class.new.skip? }
-
-    it 'skips when Geo is disabled' do
-      allow(Gitlab::Geo).to receive(:enabled?) { false }
-
-      is_expected.to be_truthy
-    end
-
-    it 'skips when Geo is enabled but its a primary node' do
-      allow(Gitlab::Geo).to receive(:enabled?) { true }
-      allow(Gitlab::Geo).to receive(:secondary?) { false }
-
-      is_expected.to be_truthy
-    end
-
-    it 'does not skip when Geo is enabled and its a secondary node' do
-      allow(Gitlab::Geo).to receive(:enabled?) { true }
-      allow(Gitlab::Geo).to receive(:secondary?) { true }
-
-      is_expected.to be_falsey
-    end
-  end
-
-  describe '#check?' do
-    context 'with functional FDW environment', :geo_fdw do
-      it 'returns true' do
-        expect(subject.check?).to be_truthy
-      end
-    end
-  end
-end

ee/spec/lib/system_check/rake_task/geo_task_spec.rb

@@ -25,7 +25,6 @@ RSpec.describe SystemCheck::RakeTask::GeoTask do
       SystemCheck::Geo::GeoDatabaseConfiguredCheck,
       SystemCheck::Geo::DatabaseReplicationEnabledCheck,
       SystemCheck::Geo::DatabaseReplicationWorkingCheck,
-      SystemCheck::Geo::FdwEnabledCheck,
       SystemCheck::Geo::HttpConnectionCheck
     ] + common_checks
   end