MONGOID-5810 make sure we don't leak internal state via as_document (backport to 8.0-stable) #3783

Job	Run time
ruby-3.1 driver-current mongodb-5.0 server	11m 1s
ruby-3.1 driver-current mongodb-5.0 replica_set	12m 31s
ruby-3.0 driver-current mongodb-5.0 server	10m 42s
ruby-3.0 driver-current mongodb-5.0 replica_set	12m 28s
jruby-9.3 driver-current mongodb-5.0 replica_set	21m 39s
ruby-2.7 driver-current mongodb-4.4 server	10m 24s
ruby-2.7 driver-current mongodb-4.4 replica_set	12m 10s
ruby-2.6 driver-current mongodb-4.0 server	0s
ruby-2.6 driver-current mongodb-4.0 replica_set	0s
ruby-2.6 driver-current mongodb-3.6 server	0s
ruby-2.6 driver-current mongodb-3.6 replica_set	0s
ruby-3.1 driver-master mongodb-5.0 replica_set	12m 31s
ruby-3.0 driver-stable mongodb-5.0 replica_set	11m 13s
ruby-2.6 driver-oldstable mongodb-4.0 replica_set	0s
ruby-2.6 driver-min mongodb-4.0 replica_set	0s
ruby-2.6 driver-min mongodb-3.6 server	0s
ruby-3.1 driver-current mongodb-5.0 server	11m 27s
ruby-3.1 driver-current mongodb-5.0 server	10m 40s
ruby-3.0 driver-current mongodb-5.0 server	10m 40s
ruby-3.0 driver-current mongodb-5.0 server	10m 37s
ruby-3.0 driver-current mongodb-5.0 server	10m 20s
ruby-2.7 driver-current mongodb-4.0 server	0s
ruby-2.6 driver-current mongodb-4.4 server	9m 56s
ruby-2.6 driver-current mongodb-4.2 server	0s
ruby-2.6 driver-current mongodb-4.2 server	0s
ruby-2.7 driver-current mongodb-5.0 server	10m 35s
jruby-9.3 driver-current mongodb-5.0 server	18m 41s
	3h 27m 35s

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