remi reported the following test failures for 1.4.0beta1:

Fedora 28 which have mongodb 3.6.0
https://koji.fedoraproject.org/koji/taskinfo?taskID=23837728

6 failures on 32-bit arches (i686 and armv7hl)

FAILED TEST SUMMARY
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PHPC-349: APM Specification [tests/apm/overview.phpt]
Int64 type: MinValue [tests/bson-corpus/int64-valid-001.phpt]
Int64 type: MaxValue [tests/bson-corpus/int64-valid-002.phpt]
MongoDB\BSON\Timestamp constructor requires positive unsigned 32-bit
integers [tests/bson/bson-timestamp_error-003.phpt]
MongoDB\Driver\Manager::executeReadCommand()
[tests/manager/manager-executeReadCommand-001.phpt]
MongoDB\Driver\Server::executeReadCommand()
[tests/server/server-executeReadCommand-001.phpt]
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Fedora 27 which have mongodb 3.4.10
https://koji.fedoraproject.org/koji/taskinfo?taskID=23837740

10 more failures on all arches

FAILED TEST SUMMARY
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Causal consistency: $clusterTime is not sent in commands to unsupported
deployments [tests/causal-consistency/causal-consistency-011.phpt]
MongoDB\Driver\Manager::executeCommand() options (MONGOC_CMD_RAW)
[tests/manager/manager-executeCommand-004.phpt]
MongoDB\Driver\Manager::executeReadCommand()
[tests/manager/manager-executeReadCommand-001.phpt]
MongoDB\Driver\Server::executeCommand() options (MONGO_CMD_RAW)
[tests/server/server-executeCommand-006.phpt]
MongoDB\Driver\Server::executeReadCommand()
[tests/server/server-executeReadCommand-001.phpt]
MongoDB\Driver\Session spec test: Pool is LIFO
[tests/session/session-001.phpt]
MongoDB\Driver\Session spec test: session cannot be used for different
clients [tests/session/session-003.phpt]
MongoDB\Driver\Session debug output (before an operation)
[tests/session/session-debug-001.phpt]
MongoDB\Driver\Session debug output (causalConsistency=false)
[tests/session/session-debug-003.phpt]
MongoDB\Driver\Session::getLogicalSessionId()
[tests/session/session-getLogicalSessionId-001.phpt]
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