AO3-6853 Update environment configs to use safe deserialization

[richard-hajek]

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• Have you added tests for any changed functionality?
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Issue

https://otwarchive.atlassian.net/browse/AO3-6853

Purpose

First timer issue - renaming YAML.load into YAML.load_safe, I tested it according to instructions in the Jira ticket, found no issues.

Credit

Richard Hajek, he/him, I have the Jira account

[Bilka2]

Hi!

Thank you so much for this pull request. Someone will be along to review it soon.

Slavalamp already updated the Jira issue status to In Review and assigned it to you so no one will mistakenly create a duplicate pull request. Additionally, I've updated your Jira account to have the ability to comment on, assign, and transition issues.

Thanks again for contributing! If you have any questions, you can contact us at the same email address listed above.

[richard-hajek]

Sorry for the messy commit history, I confused Rails.root and rails_root

[Bilka2]

Looks good, thank you!