Delivery of unexpected message after NACK

[jmalloc]

This could just be a flaky test, but recording here before the build information is lost:

107 type Queue
108 /home/runner/work/verity/verity/queue/queue_test.go:20
109   when the queue is running
110   /home/runner/work/verity/verity/queue/queue_test.go:86
111     func Pop()
112     /home/runner/work/verity/verity/queue/queue_test.go:96
113       when the queue is not empty
114       /home/runner/work/verity/verity/queue/queue_test.go:119
115         when the message at the front of the queue is not-ready for handling
116         /home/runner/work/verity/verity/queue/queue_test.go:146
117           unblocks if a nack'd message jumps the queue [It]
118           /home/runner/work/verity/verity/queue/queue_test.go:173
119 
120           Expected no difference, got:
121                 parcel.Parcel{
122                 	Envelope: Inverse(protocmp.Transform, protocmp.Message{
123                 		"@type":          s"dogma.interop.v1.envelope.Envelope",
124                 		"causation_id":   string("<cause>"),
125                 		"correlation_id": string("<correlation>"),
126               - 		"created_at":     string("2021-06-27T14:11:28.522451508Z"),
127               + 		"created_at":     string("2021-06-27T14:11:28.522425108Z"),
128                 		"data": []uint8{
129                 			... // 9 identical elements
130                 			0x22,
131                 			0x41,
132               - 			0x32,
133               + 			0x31,
134                 			0x22,
135                 			0x7d,
136                 		},
137               - 		"description":        string("{A2}"),
138               + 		"description":        string("{A1}"),
139                 		"media_type":         string("application/json; type=MessageA"),
140               - 		"message_id":         string("<message-1>"),
141               + 		"message_id":         string("<message-0>"),
142                 		"portable_name":      string("MessageA"),
143               - 		"scheduled_for":      string("2021-06-27T14:11:28.522451608Z"),
144                 		"source_application": protocmp.Message{"@type": s"dogma.interop.v1.envelope.Identity", "key": string("<app-key>"), "name": string("<app-name>")},
145                 		"source_handler":     protocmp.Message{"@type": s"dogma.interop.v1.envelope.Identity", "key": string("<handler-key>"), "name": string("<handler-name>")},
146                 		"source_instance_id": string("<instance>"),
147                 	}),
148               - 	Message:      fixtures.MessageA{Value: string("A2")},
149               + 	Message:      fixtures.MessageA{Value: string("A1")},
150               - 	CreatedAt:    s"2021-06-27 14:11:28.522451508 +0000 UTC",
151               + 	CreatedAt:    s"2021-06-27 14:11:28.522425108 +0000 UTC",
152               - 	ScheduledFor: s"2021-06-27 14:11:28.522451608 +0000 UTC",
153               + 	ScheduledFor: s"0001-01-01 00:00:00 +0000 UTC",
154                 }
155               
156 
157           /home/runner/work/verity/verity/queue/queue_test.go:188