Fix Validation Violation Localization

[AltayAkkus]

1. Why is this change necessary?

To fix #2902

2. What does this change do, exactly?

Add the correct snippets, and improve consistent dotting in the fallback messages.

3. Describe each step to reproduce the issue or behaviour.

Create a random promotion and cause a error (place the end date before the start date)
See that the text is english

4. Please link to the relevant issues (if any).

#2902

5. Checklist

• I have rebased my changes to remove merge conflicts
• I have written tests and verified that they fail without my change
• I have created a changelog file with all necessary information about my changes
• I have written or adjusted the documentation according to my changes
• This change has comments for package types, values, functions, and non-obvious lines of code
• I have read the contribution requirements and fulfil them.

[shyim]

@AltayAkkus how is the progress here?

[shyim]

Hey,

I will close this PR as it's inactive for a while. Feel free to create a new one when you applied the requested changes