http2: should return a stream if asked nicely failed

[flaky-bot]

This test failed!

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---

commit: 3219c11
buildURL: Build Status, Sponge
status: failed

Test output

Timeout of 600000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves. (/tmpfs/src/github/nodejs-googleapis-common/build/system-test/test.http2.js)
Error: Timeout of 600000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves. (/tmpfs/src/github/nodejs-googleapis-common/build/system-test/test.http2.js)
    at listOnTimeout (internal/timers.js:549:17)
    at processTimers (internal/timers.js:492:7)