If we have multiple consumers of service info asking the same question over and over they all get asked even though we only need to ask once. This can generate excessive amount of network traffic.

There was also a problem with ServiceInfo.async_request would ask questions that would get suppressed by the duplicate question suppression of the responder. We now delay the question to ensure it will not get asked in the suppression window. Now that python-zeroconf ServiceInfo is aware of the question history, the problem became visible because it was unable to get the expected answers from another python-zeroconf instance.

fixes #1337

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testing history:

• review logs
• look for leaks
• run profile
• py-spy to look for regressions
• check TimerHandle dump
• homekit testing