Test case observations from observability now give more detail about
why a test case failed or was abandoned (issue #3845). "metadata"
includes a new "status_reason_location" key: a "filename:lineno"
location for the "status_reason", if known - for example the location
of a failing "assume()" call, the ".filter()" call whose predicate
rejected the last drawn value, or the exception for failing tests.
Test cases which exceeded the maximum allowed size now also report a
nonempty "status_reason".
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