Update pt_BR django.po

[sol2070]

Description

Fix the brazilian portuguese translation for "Stopped Reading". It was translated as something like "Conclude reading", making the title of the abandoned books section incomprehensible.

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What type of Pull Request is this?

• Bug Fix
• Enhancement
• Plumbing / Internals / Dependencies
• Refactor

Does this PR change settings or dependencies, or break something?

• This PR changes or adds default settings, configuration, or .env values
• This PR changes or adds dependencies
• This PR introduces other breaking changes

Details of breaking or configuration changes (if any of above checked)

Documentation

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Tests

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