Ignore build directories in integration tests
Ignore build directories in integration tests

Summary: We mostly ignore buck-out properly for integration tests (AbstractWorkspace), but TestWithBuckd doesn't. Make sure we're not overloading anything in watchman by watching a ton of files we don't need to watch.

Reviewed By: bobyangyf

shipit-source-id: 85796e5561ee031811d2a856af0c9976f1315c79

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