AO3-6676 Remove participant memoization causing Leave button to appear on all collection blurbs #3778

Job	Run time
rake db:otwseed	1m 19s
rspec spec/controllers	10m 10s
rspec spec/models	5m 18s
rspec --exclude-pattern 'spec/{controllers,models}/*/.rb'	4m 58s
cucumber features/admins	4m 43s
cucumber features/bookmarks	5m 6s
cucumber features/collections	5m 32s
cucumber features/comments_and_kudos	6m 17s
cucumber features/gift_exchanges	6m 35s
cucumber features/importing	2m 41s
cucumber features/other_a	9m 58s
cucumber features/other_b	5m 58s
cucumber features/prompt_memes_a	3m 48s
cucumber features/prompt_memes_b	3m 57s
cucumber features/prompt_memes_c	5m 14s
cucumber features/search	5m 59s
cucumber features/tag_sets	3m 8s
cucumber features/tags_and_wrangling	6m 6s
cucumber features/users	4m 50s
cucumber features/works	14m 2s
	1h 55m 39s

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