fix: document update would error when updating language

[odrakes-cpr]

Description

• turns out we were trying to access the language record/model to update the document relationship, we were filtering by language name field and providing it the language code

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Type of change

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How Has This Been Tested?

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Reviewer Checklist

• DB_CLIENT DEPENDENCY IS ON THE LATEST VERSION
• The PR represents a single feature (small drive-by fixes are also ok)
• The PR includes tests that are sufficient for the level of risk
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[linear]

APP-200 Document update fails with status code 503 when changing language

[jamesgorrie]

No tests? 😢
But fixes the bug!

[odrakes-cpr]

No tests? 😢 But fixes the bug!

ahhh sorry @jamesgorrie , this was in a state of limbo - whilst i deliberated fixing it on the front end, which I have decided to do .. so closing this one

climatepolicyradar/navigator-admin-frontend#162

[odrakes-cpr]

Fixing this bug on the frontend instead of making code changes in the backend to ensure consistency between the create and update endpoints.

climatepolicyradar/navigator-admin-frontend#162