Remove duplicate react-i18next mocks

[mlqn]

Description

Removed redundant mocks of react-i18next as it's already mocked in setupTests.

Verification

• [x] Your code builds clean without any errors or warnings
• [x] Manual testing done (required)

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 91.40%. Comparing base (d53c10a) to head (a189773).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #12927 +/- ## ========================================== - Coverage 91.41% 91.40% -0.02% ========================================== Files 1397 1397 Lines 19740 19740 Branches 2384 2384 ========================================== - Hits 18046 18043 -3 Misses 1432 1432 - Partials 262 265 +3 ```

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