MONGOID-5809: remove ruby -w warnings #3847

Job	Run time
ruby-3.3 drv:current db:7.0 rails: fle: replica_set	13m 59s
ruby-3.2 drv:current db:6.0 rails: fle: replica_set	13m 37s
ruby-3.1 drv:current db:6.0 rails: fle: replica_set	13m 52s
ruby-3.0 drv:stable db:6.0 rails: fle: replica_set	13m 52s
ruby-3.3 drv:current db:7.0 rails:8.0 fle:helper server	11m 58s
ruby-3.2 drv:current db:7.0 rails:7.2 fle:helper server	11m 54s
ruby-3.2 drv:current db:7.0 rails:7.1 fle:helper server	11m 59s
ruby-3.1 drv:current db:7.0 rails:7.0 fle:helper server	12m 24s
ruby-3.1 drv:current db:6.0 rails:6.1 fle:helper server	12m 19s
ruby-3.0 drv:current db:6.0 rails:6.1 fle:helper server	12m 7s
ruby-3.0 drv:current db:6.0 rails:6.0 fle:helper server	12m 18s
jruby-9.4 drv:current db:6.0 rails:6.0 fle:helper server	20m 48s
ruby-3.1 drv:current db:5.0 rails: fle: replica_set	13m 21s
ruby-2.7 drv:current db:4.4 rails: fle: replica_set	13m 33s
	3h 8m 1s

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