Remove unnecessary context from GitHub client spec

spec/lib/gitlab/github_import/client_spec.rb

@@ -62,12 +62,10 @@ describe Gitlab::GithubImport::Client, lib: true do
     end
   end
 
-  context 'when rate limit is disabled' do
-    it 'does not raise error' do
-      stub_request(:get, /api.github.com/)
-      allow(client.api).to receive(:rate_limit!).and_raise(Octokit::NotFound)
+  it 'does not raise error when rate limit is disabled' do
+    stub_request(:get, /api.github.com/)
+    allow(client.api).to receive(:rate_limit!).and_raise(Octokit::NotFound)
 
-      expect { client.issues }.not_to raise_error
-    end
+    expect { client.issues }.not_to raise_error
   end
 end