Update ActiveSupport::TimeZone.[]

[ksss]

6.0: https://api.rubyonrails.org/v6.0.6.1/classes/ActiveSupport/TimeZone.html#method-c-5B-5D
7.0: https://api.rubyonrails.org/v7.0.8.4/classes/ActiveSupport/TimeZone.html#method-c-5B-5D

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/merge