updated czech translation (#784)

## Description

<!-- Describe your changes in detail here. -->

Fixes #(issue) <!-- Remove this, if your PR doesn't fix any tracked
issue. -->

## Type of change

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the box that apply. -->
- [ ] Bugfix (Change which fixes a issue)
- [ ] New feature (Change which adds new functionality)
- [ ] Enhancement (Change which slightly improves existing code)
- [ ] Breaking change (This change will introduce incompatibility with
existing functionality)

## Changelog <!-- This is optional, but highly appreciated. -->

- Fixed …
- Added …

## Testing

- [ ] I have tested my changes and verified that they work as expected
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merge. -->

### How to test the changes

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information on how to test your changes. -->
No information provided.