Merge branch 'sh-suppress-env-leaks' into 'master'

Prevent ENV from leaking variables in CI output

See merge request gitlab-org/gitlab-ce!19607

qa/spec/support/stub_env.rb

@@ -32,6 +32,8 @@ module Support
       allow(ENV).to receive(:[]).and_call_original
       allow(ENV).to receive(:key?).and_call_original
       allow(ENV).to receive(:fetch).and_call_original
+      # Prevent secrets from leaking in CI
+      allow(ENV).to receive(:inspect).and_return([])
       add_stubbed_value(STUBBED_KEY, true)
     end
   end