Remove test for 'ldap' provider special case

spec/lib/gitlab/ldap/config_spec.rb

@@ -16,19 +16,5 @@ describe Gitlab::LDAP::Config do
     it "raises an error if a unknow provider is used" do
       expect{ Gitlab::LDAP::Config.new 'unknown' }.to raise_error
     end
-
-    context "if 'ldap' is the provider name" do
-      let(:provider) { 'ldap' }
-
-      context "and 'ldap' is not in defined as a provider" do
-        before { Gitlab::LDAP::Config.stub(providers: %w{ldapmain}) }
-
-        it "uses the first provider" do
-          # Fetch the provider_name attribute from 'options' so that we know
-          # that the 'options' Hash is not empty/nil.
-          expect(config.options['provider_name']).to eq('ldapmain')
-        end
-      end
-    end
   end
 end