Upgrade Rails to 7.1.5.2

What does this MR do and why?

Upgrades Rails to the next patch release

The only meaningful diffs are in:

1. ActiveStorage which we don't use: https://my.diffend.io/gems/activestorage/7.1.5.1/7.1.5.2
2. ActiveRecord which only affects logging to the terminal: https://my.diffend.io/gems/activerecord/7.1.5.1/7.1.5.2

References

• https://rubyonrails.org/2025/8/13/Rails-Versions-8-0-2-1-7-2-2-2-and-7-1-5-2-have-been-released
• Related to #564387

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