Add CHANGELOG entries for 8.9.9, 8.10.9, and 8.11.6
Add CHANGELOG entries for 8.9.9, 8.10.9, and 8.11.6

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Signed-off-by: Rémy Coutable <4ea0184b9df19e0786dd00b28e6daa4d26baeb3e@rymai.me>

gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab