[DOC] Suppress documentation for internals #572

Job	Run time
ruby-versions / Generate Ruby versions	3s
ubuntu-24.04 3.0	15s
ubuntu-24.04 2.7	28s
ubuntu-24.04 3.1	20s
ubuntu-24.04 3.2	19s
ubuntu-24.04 truffleruby-head	47s
ubuntu-24.04 head	18s
ubuntu-24.04 3.3	21s
ubuntu-24.04 debug	29s
ubuntu-24.04 3.4	17s
ubuntu-24.04 jruby-head	1m 16s
ubuntu-22.04 3.4	21s
ubuntu-22.04 debug	25s
ubuntu-22.04 3.2	19s
ubuntu-22.04 jruby-head	1m 12s
ubuntu-22.04 3.0	14s
ubuntu-22.04 3.3	19s
ubuntu-22.04 2.7	31s
ubuntu-22.04 truffleruby-head	40s
ubuntu-22.04 head	14s
ubuntu-22.04 3.1	13s
	9m 21s

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